Stable and Unstable feature

I forked from the @leopro branch, and I completed the feature he started.

I created a new Class called `Package`. This class decorate the `Api Package` and add our domain functionality as `latest stable` and `latest unstable`.

I killed `Badger` a service that did too much differents things.

fix #22 #6 

I created `PackageManager` that create, convert, and parse the `Package` object.

I've backuped everythings on a pendrive and I lost the @leopro commits :( I'm trying to restore.