Allow users to pick the media's source type

[Fleker]

Right now the player goes through a convoluted guess-and-check process to determine what kind of media you're playing (HTTP Progressive, HLS, etc.).

It may be better for users to pick this. It would simplify the code on my end, since I don't have to call this loop and handle exceptions, and it would be easier to extend to new formats in the future.

[nextux]

Maybe if a legacy user has just updated, or if the particular setting is missing in the json, to have it assume the content type is HLS.