Fix openstackdocs theme usage

1. What is the problem?
The tox.ini file was not installing the _openstackdocstheme_ python
module, as consequence the documentation was generated with
`defuault` theme.

2. What is the solution for the problem?
Remove the use of pbr flavors

* https://julien.danjou.info/blog/2017/packaging-python-with-pbr

3. What the features need to be implemented to the tricircleclient
to realize the solution?
None

Change-Id: I6f30ae3662a4b448c281a367924f0b87b5d909dc

doc/source/index.rst

@@ -1,9 +1,8 @@
 Python bindings and command line tool to the Tricircle API
-=========================================================
+==========================================================
 
-This is a client for `OpenStack Tricircle API`_. There's :doc:`a Python API <api>` (the
-:mod:`tricircleclient` module), and a :doc:`command-line script <shell>`
-(installed as :program:`tricircle`). Each implements the entire Tricircle API.
+This is a client for OpenStack Tricircle API. There's :doc:`a Python API <api>` (the
+:mod:`tricircleclient` module). Each implements the entire Tricircle API.
 
 .. seealso::
 

test-requirements.txt

@@ -9,3 +9,4 @@ testrepository>=0.0.18 # Apache-2.0/BSD
 testtools>=1.4.0 # MIT
 sphinx>=1.6.2 # BSD
 openstackdocstheme>=1.11.0 # Apache-2.0
+hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0

tox.ini

@@ -31,7 +31,6 @@ deps = hacking<0.13,>=0.12
 commands = flake8
 
 [testenv:venv]
-deps = .[test,doc]
 commands = {posargs}
 
 [testenv:cover]
@@ -40,7 +39,6 @@ commands =
   coverage report --fail-under=81 --skip-covered
 
 [testenv:docs]
-deps = .[test,doc]
 commands =
    python setup.py build_sphinx
 

tricircleclient/exceptions.py

@@ -119,6 +119,7 @@ def from_response(response, method=None):
     """Return an instance of one of the ClientException on an requests response.
 
     Usage::
+
         resp, body = requests.request(...)
         if resp.status_code != 200:
             raise from_response(resp)