[SP] Disable some JA hardcoded real cvars in UI if running JK2 mode.
[MP] Fixed an issue introduced during server side demo addition which introduced player colors and extended ascii being stripped from names.

This didn't show up in-game but it would have showed up in external tools receiving the player list /serverstatus, ingame browser player list, or rcon status etc.
Merge branch 'master' into rend2