Googlecrawl

Added 
A. verify_course_access function in steps controller 
B. request_from_cf in application controller

Those check:
1. Referrer is not from CF: OK show the course page
2. Referrer is undefined i.e. user typed in the url directly or come from a bookmark or a site that does not send referrer: NOT OK. Render login page.
3. Referrer is from CF:
a) user is logged in and has access to the course: OK
b) user is logged in and do not have access to the course: NOT OK. Redirect to course page. 
c) user is not logged in: NOT OK. Render login page.