Control Swap

changelog (mainly focused on making adventure maps playable with controlswap):

• added a command /controlswap treatTeamAsPlayer <true/false> that treats a whole team as one person (ex: commands like /give @a and /effect @a are not duplicated, while commands like /title @s or /tellraw @s display to all players in the team)
• shared inventory is now always active in a team, even if controlswap isn't running
• added persistent gamemode (no more forced survival yayy)
• fixed bug where /controlswap add @a during a running game would freeze all players in place
• inventory and playerstate should now save properly on server/world close