NEW GriefPrevention Support with ifPlayerMustBeOnHisClaim condition

Fix the placeholder %block%

Fix a little problem with /ei giveslot

New now you can choose the option of your activator with two different methods LEFT CLICK = down RIGHT CLICK = up

Some parts of the code improved !

New player conditions:
IfIsInTheAir : true / false (If the player must be in the air (no block under him))
IfIsOnTheBlock:
- LIST
- OF BLOCKS
- DIRT
- SAND
(If the player must be on this blocks) (default = empty = all blocks accepted)