[ussuri][goal] Drop python 2.7 support and testing

OpenStack is dropping the py2.7 support in ussuri cycle.

Complete discussion & schedule can be found in
- http://lists.openstack.org/pipermail/openstack-discuss/2019-October/010142.html
- https://etherpad.openstack.org/p/drop-python2-support

Ussuri Communtiy-wide goal:
https://governance.openstack.org/tc/goals/selected/ussuri/drop-py27.html

Switch to modern sphinx-build and using openstackdocstheme
(note that repo is not building and publishing docs, docs building works
locally with these changes).

Change-Id: I9542c1dba3f339c2acece83d7d2b5726c1c3e2bc

.zuul.yaml

@@ -1,6 +1,4 @@
 - project:
     templates:
-      - openstack-python-jobs
+      - openstack-python3-ussuri-jobs
-      - openstack-python35-jobs
-      - openstack-python36-jobs
       - check-requirements

doc/requirements.txt

@@ -0,0 +1,2 @@
+openstackdocstheme>=1.18.1 # Apache-2.0
+sphinx!=1.6.6,!=1.6.7,>=1.6.2 # BSD

doc/source/conf.py

@@ -12,10 +12,6 @@
 # All configuration values have a default; values that are commented out
 # serve to show the default.
 
-import sys
-import os
-import shlex
-
 # If extensions (or modules to document with autodoc) are in another directory,
 # add these directories to sys.path here. If the directory is relative to the
 # documentation root, use os.path.abspath to make it absolute, like shown here.
@@ -32,6 +28,7 @@ import shlex
 extensions = [
     'sphinx.ext.autodoc',
     'sphinx.ext.intersphinx',
+    'openstackdocstheme'
 ]
 
 # Add any paths that contain templates here, relative to this directory.
@@ -53,14 +50,11 @@ project = u'microversion-parse'
 copyright = u'2016, OpenStack'
 author = u'OpenStack'
 
-# The version info for the project you're documenting, acts as replacement for
+# openstackdocstheme options
-# |version| and |release|, also used in various other places throughout the
+repository_name = 'openstack/microversion-parse'
-# built documents.
+bug_project = 'microversion-parse'
-#
+bug_tag = ''
-# The short X.Y version.
+html_theme = 'openstackdocs'
-version = u'0.1.0'
-# The full version, including alpha/beta/rc tags.
-release = u'0.1.0'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
@@ -140,7 +134,7 @@ todo_include_todos = False
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
-html_static_path = ['_static']
+# html_static_path = ['_static']
 
 # Add any extra paths that contain custom files (such as robots.txt or
 # .htaccess) here, relative to this directory. These files are copied

setup.cfg

@@ -5,26 +5,20 @@ description-file = README.rst
 author = OpenStack
 author-email = openstack-discuss@lists.openstack.org
 home-page = http://www.openstack.org/
+python-requires = >=3.6
 classifier =
     Environment :: OpenStack
     Intended Audience :: Information Technology
     License :: OSI Approved :: Apache Software License
     Operating System :: POSIX :: Linux
     Programming Language :: Python
-    Programming Language :: Python :: 2
-    Programming Language :: Python :: 2.7
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.5
     Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3 :: Only
+    Programming Language :: Python :: Implementation :: CPython
 
 [files]
 packages =
     microversion_parse
 
-[build_sphinx]
-all_files = 1
-build-dir = doc/build
-source-dir = doc/source
-
-[bdist_wheel]
-universal=1

test-requirements.txt

@@ -1,7 +1,5 @@
-hacking>=0.10.2,<0.11 # Apache-2.0
+hacking>=2.0,<2.1 # Apache-2.0
 coverage>=3.6 # Apache-2.0
-sphinx!=1.2.0,!=1.3b1,<1.3,>=1.1.2 # BSD
-oslosphinx!=3.4.0,>=2.5.0 # Apache-2.0
 stestr>=1.0.0 # Apache-2.0
 testtools>=1.4.0 # MIT
 gabbi>=1.35.0 # Apache-2.0

tox.ini

@@ -1,9 +1,10 @@
 [tox]
-minversion = 2.0
+minversion = 3.1.1
 skipsdist = True
 # If you want pypy or pypy3, do 'tox -epypy,pypy3', it might work!
 # And you can get coverage with 'tox -ecover'.
-envlist = py27,py36,py35,pep8
+envlist = py36,py35,pep8
+ignore_basepython_conflict = True
 
 [testenv]
 deps = -r{toxinidir}/requirements.txt
@@ -13,20 +14,16 @@ usedevelop = True
 commands = stestr run {posargs}
 
 [testenv:venv]
-basepython = python3
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 commands = {posargs}
 
 [testenv:pep8]
-basepython = python3
-deps = hacking
 usedevelop = False
 commands =
     flake8
 
 [testenv:cover]
-basepython = python3
 setenv = PYTHON=coverage run --source microversion_parse --parallel-mode
 commands =
     coverage erase
@@ -38,10 +35,10 @@ whitelist_externals =
     find
 
 [testenv:docs]
-basepython = python3
+deps = -r{toxinidir}/doc/requirements.txt
 commands =
     rm -rf doc/build
-    python setup.py build_sphinx
+    sphinx-build -W --keep-going -b html -d doc/build/doctrees doc/source doc/build/html
 whitelist_externals =
     rm