Issue with the default config setting for new feature fixed.

Config for dropping on full.

Fixes bug preventing plugin running on versions below 1.16.

Changes:

• Added per item permissions "autopickup.item.ITEM_NAME"
• Changed permission node for all items to "autopickup.item.*"
• Added permission for picking up XP automatically "autopickup.xp"
• Dropped support for 1.8, 1.9, 1.10, 1.11 & 1.12 in favour of 1.13+
• Added reload command with permission "autopickup.reload"
• Added customizable messages
• You will no longer get a permission message if you do not have permission to use AutoPick

Fixed prefix and nopermission messages not working.
Code was unimplemented.

Added autopickup.*
It will now drop items if the players inventory is full.
No longer requires a pickaxe.