Fix for explorer job not working. ken-kentan found an obvious mistake I made and broke explorer job... Stupid me...
Remade part of explorer job handling to be more stable. Previous explorer table will get removed and replaced with new one. More compact one, fewer issues.
Added new command to check who visited chunk with /jobs explored
Fixed issue with player limits not being correctly loaded, to be more specific, not being loaded at all in some situations and resetting them.
Fix for wrong bonus/penalty values in GUI when browsing jobs.
