Stubs
libspotify
Embed LUA
Modify Lua slightly

* Silence Clang warnings
* Prevent tweaking LUA include PATH with environment
* Hardcode LUA include path to just what we want
jf-JSON v4

Pure Lua JSON implementation, should be replaced at some point though as apparently it is very slow relative to a C implementation. Mostly though, we won't notice that.
Initial Rackmate implementation