Python3 by default

Set all the tox environments to be python3 *except* venv2.
Set the trove data mostly because we can.

Change-Id: Ib65e84c7da16683f70657a3bc8e9b9ccdb8f1c8a

setup.cfg

@@ -12,8 +12,9 @@ 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 :: 3.5
+    Programming Language :: Python :: 3.6
 
 [files]
 packages = openstack_election

tox.ini

@@ -4,6 +4,7 @@ minversion = 2.0
 skipsdist = True
 
 [testenv]
+basepython = python3
 usedevelop = True
 install_command = pip install -U {opts} {packages}
 setenv = VIRTUAL_ENV={envdir}
@@ -25,10 +26,6 @@ commands = {posargs}
 basepython = python2
 commands = {posargs}
 
-[testenv:venv3]
-basepython = python3
-commands = {posargs}
-
 [testenv:docs]
 commands = python setup.py build_sphinx