Drop python 2

Remove python 2 support, use python3 as basepython in tox everywhere.

Change-Id: I487ad8a7e1c30b60917c33ccefc337caf218484b

setup.cfg

@@ -13,10 +13,9 @@ classifier =
     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 :: 3.6
+    Programming Language :: Python :: 3.7
 
 [global]
 setup-hooks =
@@ -33,11 +32,3 @@ data_files =
 console_scripts =
     gerrit-dash-creator = gerrit_dash_creator.cmd.creator:main
     gerrit-bug-dash = gerrit_dash_creator.cmd.bugs:main
-
-[build_sphinx]
-source-dir = doc/source
-build-dir = doc/build
-all_files = 1
-
-[upload_sphinx]
-upload-dir = doc/build/html

tox.ini

@@ -1,11 +1,11 @@
 [tox]
 minversion = 1.6
-envlist = py36,py27,pypy,pep8,checksyntax,dashboards
+envlist = py36,pypy,pep8,checksyntax,dashboards
 skipsdist = True
 
 [testenv]
+basepython = python3
 usedevelop = True
-install_command = pip install -U {opts} {packages}
 setenv =
    VIRTUAL_ENV={envdir}
 deps = -r{toxinidir}/requirements.txt
@@ -13,23 +13,18 @@ deps = -r{toxinidir}/requirements.txt
 whitelist_externals = bash
 
 [testenv:pep8]
-basepython = python3
 commands = flake8
 
 [testenv:venv]
-basepython = python3
 commands = {posargs}
 
 [testenv:checksyntax]
-basepython = python3
 commands = python gerrit_dash_creator/cmd/creator.py --check-only dashboards
 
 [testenv:cover]
-basepython = python3
 commands = python setup.py testr --coverage --testr-args='{posargs}'
 
 [testenv:docs]
-basepython = python3
 commands =
 # not happy with generated dashboard pages
 #  doc8 -e .rst doc CONTRIBUTING.rst HACKING.rst README.rst
@@ -45,13 +40,11 @@ builtins = _
 exclude=.venv,.git,.tox,dist,doc,*openstack/common*,*lib/python*,*egg,build
 
 [testenv:dashboards]
-basepython = python3
 commands =
   bash -c "tools/generate_dashboards.sh"
   sphinx-build -b html doc/source/ doc/build/html
 
 [testenv:bindep]
-basepython = python3
 # Do not install any requirements. We want this to be fast and work even if
 # system dependencies are missing, since it's used to tell you what system
 # dependencies are missing! This also means that bindep must be installed