Switch to using hostname from Ussuri onward

This corresponds to the upstream change titled:
"Use hostname to avoid clash with section".

This avoids a clash with the section of the same name.

An ussuri masakarimonitors.conf template is added that
uses the hostname config option. The base template continues
to use the host config option for older release, inline with
upstream.

This change also updates tox.ini, src/tox.ini, and adds pip.sh
from centrally managed release-tools.

Closes-Bug: #1941643
Change-Id: I4b5b528cf24477746bf7ff6ffedfef0b13d91816

src/templates/ussuri/masakarimonitors.conf

@@ -0,0 +1,35 @@
+# WARNING: Maintained by Juju.
+# All manual changes will be overridden.
+
+[DEFAULT]
+debug = {{ options.debug }}
+hostname = {{ options.hostname }}
+[api]
+{% if options.use_internal_endpoints == True -%}
+api_interface = internal
+{% else %}
+api_interface = public
+{% endif -%}
+auth_url = {{ identity_credentials.auth_protocol }}://{{ identity_credentials.auth_host }}:{{ identity_credentials.auth_port }}
+project_domain_name = {{ identity_credentials.credentials_project_domain_name }}
+user_domain_name = {{ identity_credentials.credentials_user_domain_name }}
+project_name = {{ identity_credentials.credentials_project }}
+username = {{ identity_credentials.credentials_username }}
+password = {{ identity_credentials.credentials_password }}
+project_domain_id = {{ identity_credentials.credentials_project_domain_id }}
+user_domain_id = {{ identity_credentials.credentials_user_domain_id }}
+region = {{ options.region }}
+[callback]
+[cors]
+[healthcheck]
+[host]
+corosync_multicast_interfaces = ens3
+corosync_multicast_ports = 5405
+# XXX LY restrict_to_remotes is a WIP
+restrict_to_remotes = True
+disable_ipmi_check = True
+[introspectiveinstancemonitor]
+[libvirt]
+[oslo_middleware]
+[process]
+process_list_path = /etc/masakari/process_list.yaml