spearmint: Fix first connect packet is lost, no splitscreen players

Store cl_localClients when switching to challenging so that
if connect packet is lost or ignored, the retries will ask for
the same local players to be added.

It would mainly be an issue when connecting over the internet.
spearmint: Rename cl_localClients to cl_localPlayers, breaks VM compat

Q3 start server menu sets cl_localClients. Renaming it breaks existing
CGame VMs. It doesn't literly break them, but bumpped API version anyway.
Merge remote-tracking branch 'upstream/master'
spearmint: Make it easier to change VM/renderer/gamesettings filenames

Fix checking if reading game qvm and not reference it. It was checking wrong name.
Merge remote-tracking branch 'upstream/master'