Remove message "You need to sign in or sign up before continuing" #349

Remove message only during oauth process
Issue #349 - "Need to sign in  before continuing" message removed

Removed in all cases
Merge branch 'devel' into hotfix/remove_message

Resolve Conflicts:
	lib/failure_app.rb
	spec/features/doorkeeper/oauth_spec.rb
Add code comments

Someone in the future will wonder why we did this. Now they
will know.
Merge pull request #373 from 18F/hotfix/remove_message

Remove message "You need to sign in or sign up before continuing" #349