Fix the placeholder %block%

New now you to choose the option of your activator 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)

Fix the in-game deletion of the block (/eb delete {id} confirm)