Various updates:

- Add Source class to encapsulate source information
- Add Name class to represent named references
- Add shell function to decompile functions and scripts to bytecode (--debug-info parameter)
- Add Reflect.parse to non-mozilla shells (--parser parameter)
- Update Reflect.parse to match latest SpiderMonkey format
- Update dependencies
- Fix bug in WeakSet.prototype.delete returning wrong value type
- Fix unicode case folding issues in regular expressions
- Fix missing function declaration block hoisting in catch statement
- Store template call site objects in script instance instead of realm
- Other clean-up