Enhance JSON to allow repo (Lukas-W, tresf, etc)
Revert "Enhance JSON to allow repo (Lukas-W, tresf, etc)"

This reverts commit bb7f4876f18ccf581c47ea157aac369cb0991f2b.
Enhance get_github_data to accept 3rd party repos

Allow repos other than LMMS, i.e. Lukas-W, tresf, diizy, etc.  This
allows community members to maintain releases, etc without having upload
access to the main project.
Process url hash tags

- Now processes URL hashtags, i.e. download.php#linux.

Also:
- Added link to KXStudio
- Added basic file filter, ".exe", ".dmg", etc.
Added repo switching and file filter support