Finished posts branch.

posts.html is now accessible and functional from the main page. Users can view their recent posts, create new posts, see posts from people they're following and as well as posts from people following them.

Added some formatting to the accordion so long posts don't cause the page to strech - will need to do the same for show_courses.html and show_user.html since if a user has one long review the text doesn't wrap things only stretch and get ugly. But that's outside the scope of this branch!
Reverting changes to __init__.py