Add qa env

Ignores tests with flake8 completely for now.

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py27, py34, py35, py36
+envlist = py27, py34, py35, py36, qa
 [testenv]
 extras = testing
 # Overwrite the parso version (only used sometimes).
@@ -46,3 +46,7 @@ commands =
 commands =
     {envpython} -c "import os; a='{envtmpdir}'; os.path.exists(a) or os.makedirs(a)"
     {envpython} sith.py --record {envtmpdir}/record.json random {posargs:jedi}
+[testenv:qa]
+commands = flake8 {posargs:jedi}
+deps =
+extras = qa