add explanatory comments to CommentThread.to_hash
add simplecov coverage tool
add test coverage for api calls using handle_threads_query and CommentThread.to_hash
remove result caching from handle_threads_query
configure mongoid via URI
timeout unicorn after 5 seconds, since edx comment client has already given up
don't query needlessly for author_username or comment_count
refactor to use presenter.  tests passing.