Add room support

[ionizer999]

Currently when a game is going on Switches that see that, will not broadcast any information.

That makes it impossible to start a new game.

The simplest solution is to just join a room with a name (that also poses as a password).

A more comfortable solution could be to create a "Rooms" submenu and allow to join Rooms from there, marking them as locked and using color for available rooms:

- @999ers
- FreeToPlay

[Join Room] [Create Room] [Back]

But the room names would be easy to start.

Joining a room explicitly has the advantage of checking for IP conflicts before a Node joins the Room virtual network.