allow to check lobby while hosting a game.

[gfgtdf]

Often waiting for player to join your game takes a long time and during that time you cannot check the lobby for find pther possibly interresting games you would join (which are then probably not 100% exactly the game you wanted but still interesting and certainly better than waiting 10 minures.)

So what a good dolution would looks like:

• Mp stating would basicialy be merged with Mp lobby (when a game is hosted mp lobby become a tabbed windows with a lobby tab and a staging tab.)
• Mabye you could even be in multiple mp_stating/mp_wait dialogs, (as multiple tabs) at the same time. As soon as a game stats your woudl then be removed form all other games.

One technical problem here is that during the mp staging and mp lobby your'd usually have different game_configs loaded (in particular in mp campaigns like LoW that have a campaign_define). Maybe this can be solved by just having all #define s loaded then.

[ProditorMagnus]

Similar #1051