Don't reinvent git

Use Git to track changes, rather than [reinventing it](https://twitter.com/konklone/status/353960261398433793).

This not only reduces the complexity of the code, but provides for better
storage and analysis of changes over time by leveraging Git's built in
version tracking and diffing capabilities.

Additionally, now other users that fork the project can take advantage
of past crawls or perform analysis of past changes.
cleaner write block
fix for stray @ in twillo block
Merge pull request #1 from benbalter/git

Don't reinvent git