Remove old DUK_TYPE_* constants.
Remove old DUK_TYPE_* constants.

This will break compatibility for anyone using them, but oh well.

olebedev/go-duktape,fattenap/go-duktape,fattenap/go-duktape,jmptrader/go-duktape,mosolovsa/go-duktape,jmptrader/go-duktape