Use tools from paver.easy instead of our own functions.

Check out [paver.easy](https://github.com/paver/paver/blob/master/paver/easy.py). Specifically, we should wrap our destructive commands in `dry()` and print using `error()`, `info()`, and `debug()`.

Not sure if we should use `sh()` at this point since it runs it through the shell, which is almost never necessary and often a bad idea.
