fixed #2106: Addig support for javascript byte code.

The compile tool for generating bytecode is only valid for OSX now.
Next step is to make it support win32.

Issues:
* Non-ascii characters(like Chinese) can't be displayed correctly when using bytecode.
* `JohnResig Inheritance` is using functionality decompile to check whether there is a `_super` in this method. This can't work when using bytecode.