Added placeholderAPI placeholder for usertags '%powerranks_usertag%'
Added placeholderAPI for the player's current world '%powerranks_world%'
Added placeholderAPI for the player's playtime '%powerranks_playtime%'
Added placeholderAPI parsing to the chat and tablist format
Fixed color codes '&i' and '&j' not working when a different color code was right after it
Changed '/pr setrank' permission check ('powerranks.cmd.set': set all ranks | 'powerranks.cmd.set.*': set all ranks | 'powerranks.cmd.set.<rankName>': set specific rank)