Fix ready-up UI being cropped with more than 2 players

Fix lobby supporting 10 players on the 2v2 map
Fix shopkeeper disappearing

Fix game crash when a player abandons

Fix team losing if only one player disconnects

Adjust rematch UI to support 4 players

Fix exploits with lifestealer

Add 2v2 map
Make suicides count as kills for the opposing team
Respawn all trees each round

Fix "Item not allowed on this hero" showing after some time
Fix neutrals spawning too frequently after rematches

Fix games endng after one round if the game is a rematch

Fix rematch feature