Cleaned out old/out-of-date/unnecessary stuff, recreated wordlists with proper documentation.

Details:
Deleted all the django/database-related stuff.
Deleted all previously-existing wordlists.
Deleted json_tools.py and longitudinal.py as being out-of-date and unnecessary.
Modified __init__ to remove references to django/database-related stuff.
Added corpora_used.txt, which is a reference list of all the NLTK corpora used to construct the wordlists.
Added words.txt, which is a list of all the words extracted from the corpora cited in corpora_used.txt.
Added words_lowered.txt, which is the same words as in words.txt, but lowercased using .lower().
Added freqs.json, which is a json dump of a dictionary of words from words.txt and their frequencies in the list.
Added lowered_freqs.json, which is a json dump of a dictionary of words from lowered_words.txt and their frequencies in the list.
Deleted to_db.py.
Folded tools/filter.py into twitterizer.Twitterizer.
Moved auth.py out of tools and deleted tools.
Moved freq_splitter.py and splitter.py into feature_extraction.
Moved corpora_used.txt, words.txt, lowered_words.txt, freqs.json,
and lowered_freqs.json into resources.
Fixed the way Twitterizer's curse_out test works.
Rewrote README.txt to reflect the changes since the last time
I touched README.
Added feature_extraction/basic_features.py
Fixed bug in twitterizer.py
oops...fixed some bugs in twitterizer.py and parsed.py
whoops.
Merge branch 'master' of https://github.com/swizzard/tweet_stuff
minor fixes, I'm an idiot.
Changes to twitterizer to make it work again.
Changes to feature_extraction/splitter.py and /freq_splitter.py to give option
of using either lowered or non-lowered wordlists/frequencies.
bug fix in ParsedTweet.__init__
bug fixes. everything *should* work now
added error handling for urllib2.URLerror in parsed.get_unshortened_urls
fixes to parsed.py
added feature_extraction/__init__.py
changed the way twitterizer.Scrape handles refreshing streams and samples
Modifications to how twitterizer.Scrape deals with samples and streams.
Scrape.get_tweets will now auto-refresh the sample if it encounters a StopIteration error.
Removed Scrape.rescrape method as superfluous.
fix to parsed.Parsed.to_json
changed parsed.Parsed.__init__ to try and extract expanded urls from tweet JSON first before falling back to shortened URL. Hopefully this will prevent (some) 'too many redirects' errors.
moved contents of resources folder into feature_extraction