conf: Resolve Sphinx errors

This resolves all the warnings currently emitted by oslo.config for nova
and makes the output nicer looking to boot. There are still some issues
but these lie without other projects (osprofiler, oslo.db) and will be
resolved in a future update of those packages.

Change-Id: Ie4eddda36439e6746cb2d97e43b91f63d835877b

nova/conf/cells.py

@@ -522,7 +522,7 @@ rabbit://USERNAME:PASSWORD@HOSTNAME:PORT/VIRTUAL_HOST
 Possible values:
 
 The scheme can be either qpid or rabbit, the following sample shows
-this optional configuration:
+this optional configuration::
 
     {
         "parent": {
@@ -550,7 +550,6 @@ this optional configuration:
             "is_parent": false
         }
     }
-
 """)
 ]
 

nova/conf/compute.py

@@ -1121,8 +1121,8 @@ Possible values:
   ``instance_delete_interval`` to disable the delete attempts.
 
 Related options:
-* ``instance_delete_interval`` in interval_opts group can be used to disable
-  this option.
+
+* ``[DEFAULT] instance_delete_interval`` can be used to disable this option.
 """)
 ]
 

nova/conf/configdrive.py

@@ -37,14 +37,16 @@ Possible values:
 Related options:
 
 * This option is meaningful when one of the following alternatives occur:
-  1. force_config_drive option set to 'true'
+
+  1. ``force_config_drive`` option set to ``true``
   2. the REST API call to create the instance contains an enable flag for
      config drive option
   3. the image used to create the instance requires a config drive,
-     this is defined by img_config_drive property for that image.
+     this is defined by ``img_config_drive`` property for that image.
+
 * A compute node running Hyper-V hypervisor can be configured to attach
   configuration drive as a CD drive. To attach the configuration drive as a CD
-  drive, set config_drive_cdrom option at hyperv section, to true.
+  drive, set the ``[hyperv] config_drive_cdrom`` option to true.
 """),
     cfg.BoolOpt('force_config_drive',
         default=False,

nova/conf/devices.py

@@ -20,13 +20,14 @@ vgpu_opts = [
     cfg.ListOpt('enabled_vgpu_types',
         default=[],
         help="""
-A list of the vGPU types enabled in the compute node.
+The vGPU types enabled in the compute node.
 
 Some pGPUs (e.g. NVIDIA GRID K1) support different vGPU types. User can use
 this option to specify a list of enabled vGPU types that may be assigned to a
 guest instance. But please note that Nova only supports a single type in the
 Queens release. If more than one vGPU type is specified (as a comma-separated
-list), only the first one will be used. An example is as the following:
+list), only the first one will be used. An example is as the following::
+
     [devices]
     enabled_vgpu_types = GRID K100,Intel GVT-g,MxGPU.2,nvidia-11
 """)

nova/conf/guestfs.py

@@ -37,11 +37,13 @@ enable verbose debug messages. In order to use the above feature,
 "libguestfs" package must be installed.
 
 Related options:
+
 Since libguestfs access and modifies VM's managed by libvirt, below options
 should be set to give access to those VM's.
-    * libvirt.inject_key
-    * libvirt.inject_partition
-    * libvirt.inject_password
+
+* ``libvirt.inject_key``
+* ``libvirt.inject_partition``
+* ``libvirt.inject_password``
 """)
 ]
 

nova/conf/libvirt.py

@@ -154,13 +154,13 @@ root user is available, the instance won't be launched and an error is thrown.
 Be aware that the injection is *not* possible when the instance gets launched
 from a volume.
 
+*Linux* distribution guest only.
+
 Possible values:
 
 * True: Allows the injection.
-* False (default): Disallows the injection. Any via the REST API provided
-admin password will be silently ignored.
-
-*Linux* distribution guest only.
+* False: Disallows the injection. Any via the REST API provided admin password
+  will be silently ignored.
 
 Related options:
 
@@ -237,6 +237,7 @@ and/or SPICE is enabled. If the node doesn't support a graphical framebuffer,
 then it is valid to set this to False.
 
 Related options:
+
 * ``[vnc]enabled``: If VNC is enabled, ``use_usb_tablet`` will have an effect.
 * ``[spice]enabled`` + ``[spice].agent_enabled``: If SPICE is enabled and the
   spice agent is disabled, the config value of ``use_usb_tablet`` will have
@@ -500,16 +501,15 @@ Possible values:
 * ``host-passthrough``: Use the host CPU model exactly
 * ``custom``: Use a named CPU model
 * ``none``: Don't set a specific CPU model. For instances with
-``virt_type`` as KVM/QEMU, the default CPU model from QEMU will be used,
-which provides a basic set of CPU features that are compatible with most
-hosts.
+  ``virt_type`` as KVM/QEMU, the default CPU model from QEMU will be used,
+  which provides a basic set of CPU features that are compatible with most
+  hosts.
 
 Related options:
 
 * ``cpu_model``: This should be set ONLY when ``cpu_mode`` is set to
-``custom``. Otherwise, it would result in an error and the instance
-launch will fail.
-
+  ``custom``. Otherwise, it would result in an error and the instance launch
+  will fail.
 """),
     cfg.StrOpt('cpu_model',
                help="""
@@ -522,9 +522,8 @@ Possible values:
 Related options:
 
 * ``cpu_mode``: This should be set to ``custom`` ONLY when you want to
-configure (via ``cpu_model``) a specific named CPU model.  Otherwise, it
-would result in an error and the instance launch will fail.
-
+  configure (via ``cpu_model``) a specific named CPU model.  Otherwise, it
+  would result in an error and the instance launch will fail.
 * ``virt_type``: Only the virtualization types ``kvm`` and ``qemu`` use this.
 """),
     cfg.ListOpt(
@@ -548,7 +547,7 @@ to address the guest performance degradation as a result of applying the
 
 To specify multiple CPU flags (e.g. the Intel ``VMX`` to expose the
 virtualization extensions to the guest, or ``pdpe1gb`` to configure 1GB
-huge pages for CPU models that do not provide it):
+huge pages for CPU models that do not provide it)::
 
     [libvirt]
     cpu_mode = custom

nova/conf/notifications.py

@@ -74,6 +74,7 @@ Note that notifications can be completely disabled by setting ``driver=noop``
 in the ``[oslo_messaging_notifications]`` group.
 
 Possible values:
+
 * unversioned: Only the legacy unversioned notifications are emitted.
 * versioned: Only the new versioned notifications are emitted.
 * both: Both the legacy unversioned and the new versioned notifications are

nova/conf/scheduler.py

@@ -43,10 +43,12 @@ Other options are:
 Possible values:
 
 * Any of the drivers included in Nova:
-** filter_scheduler
-** caching_scheduler
-** chance_scheduler
-** fake_scheduler
+
+  * filter_scheduler
+  * caching_scheduler
+  * chance_scheduler
+  * fake_scheduler
+
 * You may also set this to the entry point name of a custom scheduler driver,
   but you will be responsible for creating and maintaining it in your setup.cfg
   file.

nova/conf/spice.py

@@ -154,6 +154,7 @@ A keyboard layout which is supported by the underlying hypervisor on this
 node.
 
 Possible values:
+
 * This is usually an 'IETF language tag' (default is 'en-us'). If you
   use QEMU as hypervisor, you should find the list of supported keyboard
   layouts at /usr/share/qemu/keymaps.

nova/conf/wsgi.py

@@ -78,12 +78,13 @@ for the original request, even if it was removed by a SSL terminating proxy.
 Possible values:
 
 * None (default) - the request scheme is not influenced by any HTTP headers
-* Valid HTTP header, like HTTP_X_FORWARDED_PROTO
+* Valid HTTP header, like ``HTTP_X_FORWARDED_PROTO``
 
 WARNING: Do not set this unless you know what you are doing.
 
 Make sure ALL of the following are true before setting this (assuming the
 values from the example above):
+
 * Your API is behind a proxy.
 * Your proxy strips the X-Forwarded-Proto header from all incoming requests.
   In other words, if end users include that header in their requests, the proxy
@@ -92,7 +93,6 @@ values from the example above):
   for requests that originally come in via HTTPS.
 
 If any of those are not true, you should keep this setting set to None.
-
 """),
     cfg.StrOpt(
         'ssl_ca_file',