Merge "Introduce fast8 tox target"

tox.ini

@@ -44,6 +44,15 @@ commands =
   # Check that all included JSON files are valid JSON
   bash -c '! find doc/ -type f -name *.json | xargs -t -n1 python -m json.tool 2>&1 > /dev/null | grep -B1 -v ^python'
 
+[testenv:fast8]
+# This is a subset of the full pep8 check which
+# only runs flake8 on the changes made since
+# HEAD-1. For a full flake8 run including checking
+# docs, just use pep8.
+basepython = python2.7
+commands =
+  bash tools/flake8wrap.sh -HEAD
+
 [testenv:functional]
 # TODO(melwitt): This can be removed when functional tests are gating with
 # python 3.x