Remove Python 2.6 support

OpenStack dropped Python 2.6 support, so let's remove it from setup.cfg
and drop the argparse requirement as it is native in Python >2.7.

Change-Id: I76be413c00bfc64f6f125d7264ee8b4fbe31a5a5

doc/source/contributing.rst

@@ -152,6 +152,6 @@ You can run tests using Tox:
 
     $ tox
 
-This will run tests under Python 2.6, 2.7 and verify `PEP 8
+This will run tests under Python 2.7 and verify `PEP 8
 <http://www.python.org/dev/peps/pep-0008/>`_ compliance. The identical test
 suite is run by OpenStack's Jenkins whenever you send a patch.

doc/source/install.rst

@@ -60,18 +60,13 @@ Now create your virtualenv.
         $ sudo pip install --upgrade setuptools
 
 To run the test suite use the following command. This will run
-against Python 2.6, Python 2.7 and run the `flake8
+against Python 2.7 and run the `flake8
 <https://flake8.readthedocs.org>`_ code linting.
 
 .. code-block:: bash
 
     $ tox
 
-.. note::
-
-    If you only have access to Python 2.6 or 2.7 locally pass
-    in `-e py26` or `-e py27` respectively.
-
 
 Configuration
 -------------

requirements.txt

@@ -4,7 +4,6 @@
 pbr>=0.6,!=0.7,<1.0
 
 anyjson>=0.3.3
-argparse
 Babel>=1.3
 # The egg=tripleo-heat-templates suffix is needed by pbr's requirements
 # processing code

setup.cfg

@@ -16,7 +16,6 @@ classifier =
     Programming Language :: Python
     Programming Language :: Python :: 2
     Programming Language :: Python :: 2.7
-    Programming Language :: Python :: 2.6
 
 [files]
 packages =

tox.ini

@@ -1,7 +1,7 @@
 [tox]
 minversion = 1.6
 skipsdist = True
-envlist = py26,py27,pep8
+envlist = py27,pep8
 
 [testenv]
 usedevelop = True