Add JavaScript function handling
Add method_missing tricks, remove useless debug lines.
Add [] syntax for JS functions
Support Ruby Proc as JS callback type
Fix GC bug
Add API to destroy a callback proc after calling for certain number of times
Refactor mrb argument fetching code
Regulate pointer mark position
Support passing array from Ruby side to JS side
Fetch field may also be used on functions
Allow get_field to use any valid type as key, this prepares for array index fetching.
Fix bug when returning a string value
Add set field method
Implement JsArray
Implement Array#toJsArray method
Add JsArray::create, JsObject::create
Implement Hash#toJsObject
Convert Ruby Hash to JS Object automatically using Hash#toJsObject
Sort EXPORTED_FUNCTIONS
Rename *_constructor with *_new