add 'determine uncancelled' to 'on player clicks'

A lot of click events seem to be cancelled by default... this adds a
determination for 'uncancelled' in the click event.
Actual usage: right-clicking a dragoncontrolstaff item while riding an
enderdragon:
normally, does nothing due to arbitrarily pre-cancellation (At least on
C-K's server)... but with a 'determine uncancelled' in the event,
right-clicking will properly cause the dragon to move downward.
I imagine plugins will cancel a lot of events that Denizen users want to
not be cancelled... so I think this should be the first of many
'uncancelled' determine options.
Correct meta error in 'on furnace smelts'

Straightforward fix, the meta information was a bit off.
Also autofixed some spacing apparently.
Merge branch 'master' of https://github.com/aufdemrand/Denizen
Change 'uncancelled' to 'cancelled:false'

David suggested this, I like it, auf does too.
Add dNPC.getLivingEntity() to fix some errors

That particular command needs a LivingEntity instead of just a regular
Entity. The function will probably be useful in the future as well.
Add new command 'despawn'

This command will despawn an NPC without permanently removing it.
Will defaultly used the linked NPC but can use a list of NPCs instead.
Update all NPC tag meta to include the n@notation

Straight-forward meta fix
Merge pull request #513 from mcmonkey4eva/master

Huge pile of commits - 'cancelled:false' in 'on player clicks', 'despawn' command, some meta corrections...