Make it usable from within other applications

[eyedeekay]

Hi, I wanted to use some of your code in another project so I made it importable. It doesn't change anything about the functionality of the application itself.

[pgaskin]

This is a good idea in general, but I'd rather keep the package update loop out of it, as it's subject to change and I'll be rewriting it for the next version (I'm planning on using fsnotify and adding caching for package metadata).