Refactor this all
Add reload command
Ignore cancelled events
Do not damage only players that actually double jumped
Ooops
Use another one method to check if player should take damage
Also apply this method to double jump to damage players that double jumped from high place to low place
Fix survival to creative mode switch after jump
No point in this variable now
Merge pull request #1 from Shevchik/master

Make players take fall damage if their finish jump loation is lower that start jump loacation.