[STYLE] ignore W504 and W605 in flake8
[STYLE] ignore W504 and W605 in flake8

W504, W605, F401, E261 and F841 are causing trouble while they where working OK before.
It's probably due to the new version of flake8.
W504 and W605 have been introduced in pycodestyle which is used by
pyflakes, but W504 should be ignored by default according to
http://pycodestyle.pycqa.org/en/latest/developer.html#id2 (bug?).

They have been added to setup.cfg for now, so automated tests can pass
again.

petrjasek/superdesk-core,mdhaman/superdesk-core,superdesk/superdesk-core,superdesk/superdesk-core,petrjasek/superdesk-core,ioanpocol/superdesk-core,mdhaman/superdesk-core,petrjasek/superdesk-core,mdhaman/superdesk-core,ioanpocol/superdesk-core,petrjasek/superdesk-core,superdesk/superdesk-core,superdesk/superdesk-core,ioanpocol/superdesk-core