Revert "Merge remote-tracking branch 'origin/pr/20'"

This reverts commit c101b564a7a5ff60850cd2f4feae723a19cf4902, reversing
changes made to 4a9a2c968ff6ac6b034f002ec50dfa1157e59254.

Conflicts:
	.travis.yml
	session_security/tests/middleware.py
	session_security/utils.py