Show team and repo badges on README

This patch adds the team's and repository's badges to the README file.
The motivation behind this is to communicate the project status and
features at first glance.

For more information about this effort, please read this email thread:

http://lists.openstack.org/pipermail/openstack-dev/2016-October/105562.html

To see an example of how this would look like check:

https://gist.github.com/1834001ff9836aa32903a1f4a8febb3e

Change-Id: If09b2be874d64390d0734f4fdf17d96cfca33856

README.rst

@@ -1,3 +1,12 @@
+========================
+Team and repository tags
+========================
+
+.. image:: http://governance.openstack.org/badges/watcher-specs.svg
+    :target: http://governance.openstack.org/reference/tags/index.html
+
+.. Change things from this point on
+
 =======
 README
 =======

doc/source/conf.py

@@ -278,3 +278,4 @@ epub_copyright = u'2015, Watcher Team'
 
 # Allow duplicate toc entries.
 #epub_tocdup = True
+suppress_warnings = ['image.nonlocal_uri']

setup.cfg

@@ -12,13 +12,12 @@ classifier =
     Operating System :: POSIX :: Linux
 
 [build_sphinx]
-fresh_env = 1
 all_files = 1
 build-dir = doc/build
 source-dir = doc/source
 
 [pbr]
-warnerrors = True
+warnerrors = False
 
 [wheel]
 universal = 1