Cleanup tempest docs a bit

This commit fixes a few things in the tempest docs. First it fixes all
of the sphinx warnings and enables fail on warn to ensure we're using
valid sphinx everywhere. It also adds a link from the configuration
guide to the sample config file.

Change-Id: I3ad645a6bbfa46b4498e1732410743e46d6eb0cb
diff --git a/HACKING.rst b/HACKING.rst
index 8e0ac44..a918f4a 100644
--- a/HACKING.rst
+++ b/HACKING.rst
@@ -72,11 +72,10 @@
 Most other assert method can include more information by default.
 For example ``self.assertIn`` can include the whole set.
 
-It is recommended to use testtools matcher for the more tricky assertions.
-`[doc] <http://testtools.readthedocs.org/en/latest/for-test-authors.html#matchers>`_
+It is recommended to use testtools `matcher`_ for the more tricky assertions.
+You can implement your own specific `matcher`_ as well.
 
-You can implement your own specific matcher as well.
-`[doc] <http://testtools.readthedocs.org/en/latest/for-test-authors.html#writing-your-own-matchers>`_
+.. _matcher: http://testtools.readthedocs.org/en/latest/for-test-authors.html#matchers
 
 If the test case fails you can see the related logs and the information
 carried by the exception (exception class, backtrack and exception info).
@@ -158,8 +157,8 @@
 sections for the test (one of those is mandatory):
 
  - A resource (part of the URL of the request): Resources needed for a test
- must be created in `setUpClass` and registered with `set_resource` e.g.:
- `cls.set_resource("server", server['id'])`
+   must be created in `setUpClass` and registered with `set_resource` e.g.:
+   `cls.set_resource("server", server['id'])`
 
  - A json schema: defines properties for a request.