Restructure repository to allow it to be used as an XBMC Repository

If you apply these changes to your repository, then your github will become the XBMC repository to allow for auto updating of your ball streams addon.

To add an update to the repo, all you need to do is:
1) Make a zip of the source folder "plugin.video.xbmc-ball-streams".
2) Rename the zip to plugin.video.xbmc-ball-streams-####.zip where the #### is your version number.
3) Place the zip in "downloads/plugin.video.xbmc-ball-streams/plugin.video.xbmc-ball-streams-####.zip"