Add escaping to Player Changes Sign

Signs need escaping to properly and safely differentiate lines.
Merge branch 'master' of https://github.com/aufdemrand/Denizen
Add flag event meta
Add tag location.direction[x].yaw

Numbers beat arbitrary text
Update the rename command's meta.

Perhaps the rename command should be edited to have an optional (<npc>)
argument. But, for now, just patch the meta.
Add playerlist argument to animatechest command

So it can be shown to more than just the linked player
Catch invalid enchantment names, throw nice error

I realize this is now being null checked twice. Yes, both checks are
needed. No, I haven't the slightest clue why.
Add tag queue.determination, clean Determine

Meta was outdated + allowed the determine command to be used multiple
times, which would leave orphan outcomes recorded.
Also inform the queue of its own ID for the sake of having a
determination tag.
Allow changing the blocks in Entity Explodes

This runs really slow, probably better to never use this feature.
Just, you know, it's there. If you want it.

Also, clean the award_achievement meta and add a todo-note.
Show a nicer error for invalid triggers

Giant unneeded stack traces are bad!
(Also switch the Reflection object errors so new users won't try to ask
specifically for auf while reporting a minor issue. Auf has more
important things to do.)
Allow giving/taking to/from offline players

This command would throw an NPE for offline players... now not only does
it not throw an error, it's fully functional thanks to Morphan's offline
player inventory code!
Add custom sounds to playsound

EG - playsound <player> random.click custom
Allow execution of custom commands

Manually calling PCPEvent is awkward but it works
Fix arbitrary Bukkit API change, allow building

I thought Bukkit was supposed to *not* randomly delete API functions...
ah well. Changed to work with the new system, but added TODOs as well.
Add Biome enter events, fixes #646

Also new event warning meta.
Also, allow the Cuboid enter/exit event load properly at startup, even
though technically no dCuboids ever are actually loaded at that time.
Even more TODO's added for the incomplete event.
Also add missing event meta
Fix player list bugs

The player list tags didn't properly compensate for offline/online
players (Even though the relevant  system was reworked twice recently...
somehow missed twice. Ack.)
They now return 100% correctly!
Fix Shoot command despawned entity NPE
Merge branch 'master' of https://github.com/Morphan1/Denizen
Merge pull request #670 from Jeebiss/master

Added <e@entity.spawn_reason>
Merge pull request #671 from mcmonkey4eva/master

Pull request for things that start with the letter E