Changes to make things actually work

It was late last night when I pushed this.

Updates:
Changed twitterizer.scrape to reflect changes to the Streaming
API/twitter v.1.10
Wrapped the tests in twitterizer.twitterizer that rely on a tweet's
text in try/except to catch KeyErrors
Wrapped the Django/db-related import stuff in __init__ in try/except to
make sure it still works if you don't have Django/my specific models
involved.
Deleted get_tweets, an older version of twitterizer.