Add support for Connection-Specific Databases

[KevinAllenWiegand]

I have 2 computers that I run MusicBee on. The location of the music files are different. I can only use one of the connections because the database of tracks doesn't distinguish between connections, and trying to use a different connection results in error popups in MusicBee because of missing files.

[kelsos]

Hey, @KevinAllenWiegand thank you for opening the issue. I have thought about this issue in the past and was almost sure I had a related issue but I cannot find it anywhere. I will see how possible that would be to implement while I am working on the rewrite of the application since it is a bigger change.