Chicken GUI options survey and questions.

[Matt Welland]

I'm starting (yet another) attempt to move a big project of mine to
Chicken 5 and now is a good time to look at other options for the GUI.
Before I do some evaluations I'm interested in hearing any thoughts
from others.

What is your preferred toolkit for making GUI apps with chicken? 

I've been using IUP, which I know and like very much. I've listed the
pros and cons (from my perspective) far below.

Alternatives to consider
------------------------

 * webview egg
 * qt-light 
 * pstk (probably not really an option, ancient look/feel).
 * kiwi (probably too limited for my needs)

Others
------

nuklear http://wiki.call-cc.org/eggref/4/nuklear,
        https://github.com/Immediate-Mode-UI/Nuklear
        looks interesting, not clear if actively supported

flutter - no egg yet but checks all modern gui boxes and
          highly portable. Comments on effort required to 
          make a binding to Chicken would be appreciated.
          BTW: No, I'm not interested in developing in dart.
          I'm sure it is a great language but I like Chicken.

My experiences with IUP
-----------------------

Pros: 
 - super easy to learn and use
 - Good range of widgets
 - decent performance

Cons:

 - native widgets can look dated across platforms
 - you are at the whim of the platform. 
       (E.g. In my case Gnome broke using bgcolor in
        buttons which I was relying on.)
 - Very difficult to install, still no Ubuntu package.