Adds tweet and content text search to bonfire.db
Adds basic interface for tweet search to app
Folds search_universe_tweets into get_universe_tweets
Normalizes URLs and adds reference to content in processed tweets
Adds fallback URL resolution if newspaper doesn't pick up a canonical link
Adds get_popular_content db query
Adds popular content to Flask app frontend
Updates comments and deletes url.py. Closes #9 for tweets; content search still WIP
Adds content fulltext search
Adds radio toggle to filter by tweet recency
Adds date filter to tweet search. Closes #10
Merge pull request #18 from NUKnightLab/la-search

Adds most popular content to app, and tweet search functionality. Content search feature is WIP.