Switched to `Broken` unit tests.
Added support for tracing (mostly for Compiler, still incomplete, more tracing in the future).
Added more stubs for X86 scheduler.
Fixed some Compiler alloc/spill bugs.
Improved allocation of variables which have home register (asmjit prefers home register now).
Fixed Assembler `LEA REG, [LABEL]` bug.
Fixed _emit to be virtual function again.