A simple scraper example

This example uses the stream API to scrape all geotagged tweets.
Currently, they are simply printed to stdout.
Ignore vim swap files
Write tweets to MongoDB
Add helper to obtain the auth tokens
Store credentials in separate file
Only retrieve english tweets
Store filename in a pseudo constant
Pass the collection to our streamer class
Error handling and minor cleanup
Exit safely on SIGINT
Automatically write credentials to file
Buffer writes to the database
Argument parsing and an initial verbosity arg
A fancy progress bar
An initial version of our tweet store

Not  fully functional yet.
Ignore .pyc files
Provide a close() method
Use our TweetStore in twentyment
Documentation and a test date range
Convert important date fields to datetime objects