Switched Lua version to LuaJIT.

We're a bit more limited now since LuaJIT doesn't have
full 5.2 API compatibility yet, but it should be fine.
GUI test: we now use SDL2 via FFI.
Seems more stable and less flickery than VCL.
Talent GUI now uses SDL.
Fixed several problems from the LuaJIT switch.
Talent GUI is now non-modal.
Inventory GUI now uses SDL.
More GUI functions have been shared.
Some minor bugs have been fixed.
Command 'dq': Drop Quest.
Compress item lists. Add skillId to skill list.
Command lqi.
Also, don't loot quest items if you already have enough.
Equip Bigger Bag.

I wish I could cast Summon Bigger Fish.
Inventory gui: store item in bank.
Fixed a few minor bugs.
Profession GUI.
Open lootable items instead of using them. Autoloot money.
Command 'bbs': Buy Bank Slot.
Inventory GUI now also shows bank.
'use' command now assigns bags to a free bank slot.
Inventory GUI now updates on inventory change.
Professions: basic Enchanting auto-target.
Profession GUI: A few bugfixes.
Quests: auto-accept escort quests.

Failure to do this would cause trouble.
Disenchant itemLinks.
Fixed lockpicking on gameobjects.