Also more closely follows the server implementation.
BeatmapInfo.OnlineBeatmapID
OnlineID
User
APIUser
APIBeatmapSet.Beatmaps
IEnumerable
PlaylistItem.Beatmap
IBeatmapInfo
I guess the changes that involved `MultiplayerTestScene` having a test user lookup cache caused this test case to false-pass silently. Added an explicit assert which ensures the added user indeed has a null `User` value.
TestMultiplayerClient
Not sure this is the best place to do so... I can foresee this class getting much larger than we want it to.
MatchRuleset