Merge pull request #378 from Skylexia/2.9

Fixing exp trading type.
[Fix] Move all enchant type perms to: essentials.enchantments.<enchant>
[Fix] Move all potion effect perms to: essentials.potions.<effect>
[Fix] Move multiple potion perm to: essentials.potions.multiple
Other perms: essentials.itemspawn.meta-(firework|firework-multiple|firework-power|name|lore|head|book|chapter|chapter-<chapter>|author|title)
[Fix] Move allowunsafe enchant perm to: essentials.enchantments.allowunsafe
[Fix] Allow /nick to change nickname case, without adding prefix character.
Fix TL key casing.
Allow potion meta to work
Instead of denying if they have perms
Merge pull request #379 from GunfighterJ/2.9

Allow potion meta to work
Protect us from npe.
Use lower locale.