Fix incorrect debugging

DebugElement was being used improperly.
Merge branch 'master' of https://github.com/mcmonkey4eva/Denizen
Merge pull request #572 from Morphan1/master

Leeeerooooy Jenkins
Merge pull request #574 from mcmonkey4eva/master

Yay pull requests
Remove unneeded debug output

@Morphan1 forgot to remove this, it seems
Clearer error message for constants, fixes #576

if constants are defined like 'default constants: x' or 'default
constants' followed by 'x:y' without a space or something like that, it
would show a big NPE stacktrace... now it has a nice clean error
message.
Add player breaks item event

EG when you use up a tool
add result output for the Adjust command

Also meta explaining how to access it... sorta. We could use some full
clear tutorial / langs explaining the save system
Add Determine "CANCELLED" to player breaks item event