Navbar changed to be the same in all html's pages

qubal_prerender.py -> New parameter to know from which view is called.
course_listing.html -> "navbar_content" django include included.
index.html -> "navbar_content" django include included.
navbar.inc -> Refactored and new comments for div tags included.
profile.html -> </head> tag fixed and new <div class="container"> tag
included to fit with the new navbar.inc included call.
views.py -> new vars "url" and "html" included for new navbar render
system.
course_listing.css -> ".span2menu" class added to fix layout bug in the
navbar.
profile.css -> "[class*="span"]" added to fix layour bug in the navbar.
index.css -> same as course_listing.css and profile.css bugs. fixed.