'killcounter.count' - only the kills of players with this permissions will be counted
'killcounter.receive' - if player kills another player he gets a message how much kills he've gained
'killcounter.seescore.self' - gives player access to /score command
'killcounter.seescore.others' - gives player access to /score <player> command
'killcounter.admin' - gives player access to all admin-command for "killcounter"