Tox: Always generate JUnit XML, run flake8.

tox.ini

@@ -1,22 +1,22 @@
-# Tox (http://tox.testrun.org/) is a tool for running tests
-# in multiple virtualenvs. This configuration file will run the
-# test suite on all supported python versions. To use it, "pip install tox"
-# and then run "tox" from this directory.
-
 [tox]
 envlist = py27, py35
 
 [testenv]
-commands = py.test --cov=dosage --cov=dosagelib --tb=short -n10
+commands = 
+    {envbindir}/py.test --cov=dosage --cov=dosagelib --tb=short -n4 \
+        --junitxml={toxworkdir}/junit-{envname}.xml
+    - {envbindir}/flake8
 passenv = TRAVIS
 # Also install optional dependencies for tests.
 deps =
-    -r{toxinidir}/requirements.txt
+    -rrequirements.txt
     pytest-xdist
     pytest-cov
     pytest-travis-fold
     cssselect
     Pillow
+    flake8
+    flake8-coding
 
 [flake8]
 # we aim for 79, but this suppresses warnings for now...