Clarify role documentation and remove duplication

The README now makes clear that MongoDB is a dependency
and the role doc itself now simply includes the README
instead of duplicating its content.

Change-Id: I4f5008166ad385619ee50486aa953a4a7dec6f3c

README.rst

@@ -1,9 +1,8 @@
 OpenStack Aodh
 ##############
-:tags: openstack, ceilometer, cloud, ansible, aodh
-:category: \*nix
 
-Role to install aodh as the alarm functionality of Telemetry
+Ansible role that installs and configures OpenStack Aodh as the alarm
+functionality of Telemetry.
 
 This role will install the following:
     * aodh-api
@@ -11,6 +10,19 @@ This role will install the following:
     * aodh-evaluator
     * aodh-notifier
 
+The role will configure Aodh to use MongoDB for data storage, but does
+not install or configure MongoDB.
+
+Default Variables
+=================
+
+.. literalinclude:: ../../defaults/main.yml
+   :language: yaml
+   :start-after: under the License.
+
+Example Playbook
+================
+
 .. code-block:: yaml
 
     - name: Install aodh services
@@ -21,4 +33,3 @@ This role will install the following:
       vars:
         external_lb_vip_address: 172.16.24.1
         internal_lb_vip_address: 192.168.0.1
-        galera_address: "{{ internal_lb_vip_address }}"

doc/source/index.rst

@@ -1,12 +1 @@
-os_aodh Docs
-============
-
-Role to install aodh as the alarm functionality of Telemetry
-
-Basic Role Example
-^^^^^^^^^^^^^^^^^^
-
-.. code-block:: yaml
-
-    - role: "os_aodh"
-      ROLE_VARS...
+.. include:: ../../README.rst