classfile: reimpl OpCode converter

classfile: fmt

vm: just Oop::Null seems ok

vm: cache pc to access fast

vm: cache codes to access fast

Update LICENSE

vm: when invoke native avoid clone

vm: cache native method

vm: extract pop_value

vm: make fn inline

vm: etract real type when needed

vm: refact

vm: refact OpCode IF in macro

vm: extract TypeArrayEnum

vm: reimpl opcode math op in macro