The "SetCurrentGameMode" ACS function doesn't print the current level's name anymore when the game mode changes successfully.

When I changed SetCurrentGameMode to reset the current level (using ChangeLevel) in 20e4330dc3ee, my intention was for the level change to be treated more like a reset (similar to GAME_ResetMap) than actually changing levels. Thus, I also want to prevent the map's name from reappearing in the console when this happens.

As a bonus, I extended the MapExit server command to send all CHANGELEVEL flags to the client(s), so they can use them when they call G_ChangeLevel (e.g. they won't briefly see the intermission screen if G_ChangeLevel was called with CHANGELEVEL_NOINTERMISSION enabled on the server's end). In addition, the ChangeLevel ACS function can't use the newly added CHANGELEVEL_HIDENAME flag because I only intended for it to be used with SetCurrentGameMode.