Fix possible NPE

I also added a check for NPC inventory locations when the NPC is in a
chunk that's not loaded.

I'll be honest, I don't know if that works.
Merge pull request #629 from Morphan1/master

I like trains
Merge pull request #628 from mcmonkey4eva/master

Fixes and features and all that, pull requested!
Add ability to give list of locations to PlaySounds. Partially addresses #626.
Merge pull request #630 from mcmonkey4eva/master

Pull request for half-commits
Merge pull request #631 from mcmonkey4eva/master

Pull request for fixing things
Merge branch 'master' of https://github.com/mcmonkey4eva/Denizen
Add - inventory close

This simply closes any inventory the player has open.
Allow tags in inventory script titles and definitions

This is mostly just for colors.
Merge branch 'master' of https://github.com/mcmonkey4eva/Denizen
Update CommandRegistry, add Inventory-related meta

This sort of explains itself...
Merge branch 'master' of https://github.com/Morphan1/Denizen