Add dependency on jitescript

https://github.com/qmx/jitescript

Will be much easier to manipulate bytecode than what is currently done...
CachingGenerator: use jitescript's CodegenUtils
CachingGenerator: more uses of CodegenUtils
More CodegenUtils usages

Deprecates basically all classes that I created.
More jitescript usage; unsuck some code
InstructionGroupCreator: get rid of label, replace with do/while
InstructionGroupCreator: more code cleanup
More code cleanup
RuleMethodRewriter: cleanup
More uses of CodegenUtils, more cleanup
More code cleanup; more annotations; more CodegenUtils usages.
One more usage of CodegenUtils
Undeprecate Factory...

The problem is with BaseVarInit; it implements this interface, and an ASM
instruction is generated for Vars to produce a value.

As such, Supplier is in fact not usable in this context since its method,
.get(), conflicts with that of Reference, which Var inherits. Attempting to
replace Factory with Supplier generates an AbstractMethodError at runtime...
Factory: add comments
VarInitClassGenerator: fix gross error in bytecode...

Wrong signature!
Var: get back to initialize with a Factory
ClassNodeInitializer: some code cleanup
Changes to ASM related classes

Jitescript has obsoleted several classes.
Some more code cleanup
More removals of unneeded files