Fix game list not being updated bug

How to reproduce:
-Start a new multiplayer game on client 1
-Go to multiplayer menu and update game list on client 2
-Start a new multiplayer game on client 2
-Leave the game on client 1
-Leave the game on client 2 and go back to multiplayer menu
The game from client 1, will now still be in the list

Fix
-Server now also sends EndGame message to all when it's recieved
-The clients handle this like join game message and refreshes the list

TODO:
-Refresh the list when multiplayer button is clicked instead?
-Reduce number of NewGame messages sent from server