Cleanup py27 support

This repo is now testing only with Python 3, so let's make
a few cleanups:
- Remove obsolete sections from setup.cfg
- Use newer openstackdocstheme version
- Remove install_command from tox.ini, the default is fine
- remove unused test-requirements.txt file

Change-Id: Id886f9816660be168cf0eead83e900435fff1ed7

requirements.txt

@@ -1,3 +1,3 @@
 pbr>=2.0.0
-openstackdocstheme
+openstackdocstheme>=1.31.2
 yasfb>=0.5.1

setup.cfg

@@ -11,14 +11,3 @@ classifier =
     Intended Audience :: Developers
     License :: OSI Approved :: Apache Software License
     Operating System :: POSIX :: Linux
-
-[build_sphinx]
-source-dir = doc/source
-build-dir = doc/build
-all_files = 1
-
-[pbr]
-warnerrors = True
-
-[upload_sphinx]
-upload-dir = doc/build/html

tox.ini

@@ -6,11 +6,9 @@ skipsdist = True
 [testenv]
 basepython = python3
 usedevelop = True
-install_command = pip install -U {opts} {packages}
 setenv =
    VIRTUAL_ENV={envdir}
 deps = -r{toxinidir}/requirements.txt
-       -r{toxinidir}/test-requirements.txt
 
 [testenv:venv]
 commands = {posargs}