refactored javascript code for show pages
refactored javascript for index pages with charts
added scope to contribution model to rank stuff
added search function for topics,questions,contributions
added validation for topic name uniqueness and wrote unit tests for topics
added twitter bootstrap, style contribution views
removed html format of home page
finished styling topic views
finished styling question views
converted student views to HAML format
got rid of html format files
converted login page to HAML format