Always parse storyboards for now. Let's not optimise this until it is necessary. It was leading to weird threading problems due to the load call in Player's async load method.
Callback was expecting the beatmap to be populated where it wasn't being.
Resolves #792
Also standardises searchable terms in beatmap metadata.
Note that this isn't a full "as intended" fix, because the full fix is quite big. I'll be saving it for a separate branch/pull-req.