Clean up and standardize landing pages

doc index.rst:
1. Update intro sentence to read as a complete sentence
2. Remove unused toctree
3. Correct heading levels (impacting side nav and correct rendering
of content)
4. Remove "Indices and Tables" section: genindex page not used,
search searches only index (not useful here)

api-ref index.rst:
1. Update intro sentence to read as a complete sentence
2. Update text around search link for consistency (move
to follow intro)
3. Add heading before toctree for consistency with other pages

releasenotes index.rst:
1. Standardize page title reST markup
2. Remove search (make consistent with other openstack release note
pages)

Story: 2004737
Task: 28801

Change-Id: I83d023c57881e03639ff6bb85b256e53f4205817
Signed-off-by: Kristal Dale <kristal.dale@intel.com>

api-ref/source/index.rst

@@ -1,13 +1,16 @@
-=======================
+====================
 stx-ha API Reference
-=======================
+====================
 
-This is the API Reference for the StarlingX High Availability / Process
-Monitoring / Service Management
+Use the StarlingX stx-ha API to manage high availability services running
+on the StarlingX OpenStack controller cluster.
+
+stx-ha API content can be searched using the :ref:`search page <search>`.
+
+API Reference
+-------------
 
 .. toctree::
    :maxdepth: 2
 
    api-ref-smapi-v1-ha
-
-:ref:`search`

doc/source/index.rst

@@ -1,11 +1,9 @@
+====================
 stx-ha Documentation
 ====================
 
-StarlingX High Availability / Process Monitoring / Service Management
-
-.. toctree::
-   :maxdepth: 2
-   :caption: Contents:
+The StarlingX stx-ha project provides high availability cluster management
+for StarlingX and OpenStack services on controllers.
 
 Release Notes
 -------------
@@ -24,7 +22,7 @@ API Reference
    API Reference <https://docs.starlingx.io/api-ref/stx-ha>
 
 Links
-=====
+-----
 
 * Source: `stx-ha`_
 * Code Review: `Gerrit`_
@@ -33,9 +31,3 @@ Links
 .. _stx-ha: https://git.starlingx.io/cgit/stx-ha/
 .. _Gerrit: https://review.openstack.org/#/q/project:openstack/stx-ha
 .. _Storyboard: https://storyboard.openstack.org/#!/project/openstack/stx-ha
-
-Indices and Tables
-==================
-
-* :ref:`search`
-* :ref:`genindex`

releasenotes/source/index.rst

@@ -1,9 +1,8 @@
+====================
 stx-ha Release Notes
-=======================
+====================
 
 .. toctree::
    :maxdepth: 2
 
    unreleased
-
-:ref:`search`