Finished update for 1.6
Mainly handling the ResourcePack changes.

Note on themes:
 - Texture pack theme list moved to craftguide:themes.txt
 - Themes listed searched in craftguide:<listed text>
 - Source type "resource" added, as clearer equivalent to "file-jar"
 - Still no in-game editor, sadly.
 - No support for multiple packs defining themes, though this MIGHT be possible in the future
- Added pack.mcmeta
 - Fixed theme loading debug setting
 - ModLoader compatibility
 - Used Minecraft.getMinecraft() more, for consistency
 - Repllaced access to Minecraft.renderEngine with Minecraft.func_110434_K(), for ModLoader compatibility.
 - Cleaned up a few unnessecary imports
 - Upgraded FML client to use @EventHandler
 - Moved item to PreInit
 - Added config for whether a crafting recipe for the item is created