Accept either String or Int, without resorting to Dynamic

A quick code sample:

`AcceptEither`, a way to accept either one type or another, without resorting to “Dynamic”, and still have the compiler type-check everything and make sure you correctly handle every situation.

Try it on try.haxe.org

The next step would be having Accept2Types, Accept3Types etc, and have a macro automatically build the code for whichever option you ask for.