[AD] Some good news for the Emscripten port.

[Max Savenkov <max.savenkov@xxxxxxxxxx>]

Since there wasn't too much interest in my port, and it was pointed out that it wasn't very useful in its current form due to need to restructure your code a lot, I decided to wait for something to change in _javascript_ world before continuing my work. Actually, I was hoping for the next JS standard which contains generators to be accepted by all browsers, but instead another thing happened. As of last release, Emscripten now contains a setting called ASYNCIFY (https://github.com/kripken/emscripten/wiki/Asyncify), which allows C++ programmers to call the new emscripten_sleep function to "pause" execution of code and give the control back to browser.

I haven't tried it yet, but from the looks of it, I think it solves the need to restructure code for Emscripten ports of Allegro-based games, and it will probably allow me to simplify port's code somewhat (but not all of it, since _javascript_ still has no usable threads).

Don't hold your breath for a quick next version, though, since I'm currently somewhat swamped with various projects. But I think I'll give it a try some time in the next month or two.