Add "General Settings" (for things like Metacritic match score threshold) #57
Description
Currently all settings are in the context of "Provider Settings". However, there are settings which are not tied to any particular provider (or at least any provider exposed to the user, as is the case with Metacritic).
In the case of Metacritic, the threshold is currently simply hardcoded (to 50). In other cases I imagine the settings are taken from environment variables. Either way, a dedicated settings UI would be good.