Invalid map for map command no longer disables SP mode

It's just pointless.
Made sv_hostname default to noname again
Remove cvar init of dmflags, timelimit, and fraglimit from server

They're only used in game, which will init them as serverinfo anyway. Allows mods developers to get rid of the cvars if they want.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	code/server/sv_init.c