Support for repos where the bundle is inside a sub-directory

This PR adds support for repositories like https://github.com/trakt/Plex-Trakt-Scrobbler so they can be used directly in this app store without the need of an extra repository to change it to the normal repository form (how the trakt plugin is currently provided in the app store).

Note, this is for a soon to be released update of Plex-Trakt-Scrobbler, and will help to simplify releases.