Clean up some twine warnings and errors

Previously, `twine check` would complain like

    warning: `long_description_content_type` missing.  defaulting to
    `text/x-rst`.
    Failed
    The project's long_description has invalid markup which will not be
    rendered on PyPI. The following syntax errors were detected:
    line 8: Error: Unexpected indentation.

Change-Id: I56539a42ca2bcff44487928e4835d71eb03bd521

README.rst

@@ -5,12 +5,13 @@ Application Features
 --------------------
 Stackalytics is a service that automatically analyzes OpenStack
 development activities and displays statistics on contribution. The features are:
- * Extraction of author information from git log, store it in the database;
- * Calculate metrics on number of lines changed (LOC) and commits;
- * Mapping authors to companies and launchpad ids;
- * Filter statistics by time, modules, companies, authors;
- * Extract blueprint and bug ids from commit messages;
- * Auto-update of database.
+
+* Extraction of author information from git log, store it in the database;
+* Calculate metrics on number of lines changed (LOC) and commits;
+* Mapping authors to companies and launchpad ids;
+* Filter statistics by time, modules, companies, authors;
+* Extract blueprint and bug ids from commit messages;
+* Auto-update of database.
 
 Quickstart
 ----------

setup.cfg

@@ -3,6 +3,7 @@ name = stackalytics
 summary = OpenStack Contribution Dashboard
 description-file =
     README.rst
+description-content-type = text/x-rst
 author = OpenStack
 author-email = openstack-discuss@lists.openstack.org
 home-page = https://www.openstack.org/