chore: Add pylint envs

This patch adds lint2 and lint3 testenvs to tox.ini for running pylint
under Python 2.7 and Python 3.3, respectively.

Change-Id: Ia73ce61fc19b0e30a6de5ad90236d41dbbf33125

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 minversion = 1.6
-envlist = py26,py27,py33,pypy,pep8
+envlist = py26,py27,py33,pypy,pep8,lint2,lint3
 skipsdist = True
 
 [testenv]
@@ -22,6 +22,16 @@ downloadcache = ~/cache/pip
 [testenv:pep8]
 commands = flake8
 
+[testenv:lint2]
+basepython = python2
+deps = pylint
+commands = pylint ./marconi ./tests -E --ignore ./openstack
+
+[testenv:lint3]
+basepython = python3
+deps = pylint
+commands = pylint ./marconi ./tests -E --ignore ./openstack
+
 [testenv:cover]
 setenv = NOSE_WITH_COVERAGE=1
 commands =
@@ -36,3 +46,4 @@ exclude = .venv*,.git,.tox,dist,doc,*openstack/common*,*lib/python*,*.egg,.updat
 
 [hacking]
 import_exceptions = marconi.openstack.common.gettextutils._
+