bug fix in gae_bingo
update exercises
update exercises
update exercises
update exercises
update exercises
added my gae sdk dir to .gitignore
#46: student progress tooltip changed to hebrew
Fix cache key generation for topic.get_filled_content_topics
#49: sort vids and exercises for display in progress report
#38: sort exercises and show only relevant in class profile
#37: browse to user profile upon clicking on chart column