Fix multi line docstring tests in hacking.py

* Fixes N403, along with docstring test
* Adds N404, multi line start
* Disable N403 and N404 until all cases are fixed
* Remove obsolote '--repeat' flag from tox.ini

Change-Id: Ibf6371efc1cdc764e66f6f7c5c4362440101f963
Merge "Fix multi line docstring tests in hacking.py"