Document and update existing hacking violations

There were no violations of H409, so I removed it from the list of
ignored violations.

Change-Id: If01de70cf83a4ca4830e2236582cbe72f15b85b4

1 files changed, 3 insertions, 1 deletions

diff --git a/tox.ini b/tox.ini
index 9385341..452e361 100644
--- a/tox.ini
+++ b/tox.ini
@@ -29,7 +29,9 @@ commands = oslo_debug_helper {posargs}
 
 [flake8]
 show-source = True
-ignore = H405,H904
+# H405: Multi line docstrings should start with a one line summary followed by
+#       an empty line.
+ignore = H405
 exclude = .tox,dist,doc,*.egg,build,./pycadf/openstack/common
 
 [hacking]