Initial operator commit
Add command line switch and compiler option for inline operators
Add more operators for inlining
Very simple implementation of benchmark
Disable operator inlining by default
Add a maximum depth parameter to Promise#trace
Align assignments
Cleanup function definition
Add some documentation to boot_class_meta()
Use more explicit names in runtime API

- rename boot_class_meta to boot_class_object
- rename boot_defclass to boot_class_alloc
Check for .rb_stub when looking for methods
Split method_missing stub helpers in smaller funcs
Enable method_missing on bridged classes

Fixes #593.

It works by adding all bridged classes to method_missing stubs subscribers list.
Rename .rb_stub to .$$stub

Ref: #583
Rename boot_module to boot_module_object

As it’s booting the object as in Module.new.
Rename $$mod to $$is_mod

For parity with $$is_class
Align assignments
Move Module#append_features to runtime.js
Extract common code into setup_module_object
Rename .__iclass to .$$iclass

ref: #583