- Mod integration can now specify a required version prefix
- Ingredients can now also be liquids
- Added some checks that should fix #87
- Temporarily disabled BuildCraft support for BC 6.1 (BC 6.0 still has support)
- Started work on BC 6.1 support (not yet functional and currently disabled)
Merge branch 'master' into 3.1

Conflicts:
	MineTweaker3-API/src/main/java/minetweaker/MineTweakerAPI.java
	MineTweaker3-API/src/main/java/minetweaker/api/item/IIngredient.java
	MineTweaker3-API/src/main/java/minetweaker/api/liquid/ILiquidStack.java
- Continued towards a compiling (but not yet complete) version of ZenCode
- Refactored and reworked the 1.7.10 implementation to fit the new ZenCode API
- Added UndoableAction class and refactored existing code to use it