obs::source_tracker allows us to do more over more versions of OBS Studio, so we are able to enumerate any and all Sources, Scenes and Transitions that weren't created private. If we were to rely on libOBS for this, we would need to limit ourselves to version 23 or higher, but with this we can go very far back - as far back as the global event system was fully supported.
The number of files in the source directory was a little bit much and just made file naming more complex than it had to be. Therefore all files were moved into subdirectories where it matters.
Filters now reside in source/filters/, Sources in source/sources/, OBS Wrappers in obs/, OBS GS Wrappers in obs/gs/, Transitions will reside in source/transitions, Graphics Helpers will be in gfx/.
