Initial commit: crawling tweet data from tweet server

tweetdatastore allows you to query to tweet server via twython
From now, you can get json dump files after running crawlingtweets.py

$ python crawlingtweets.py

You can find many text files under dumps, that include query result.
Two files which are created in root folders are used for tracking
the last tweet from tweet server with max_id and created_at for the
next query.