Feature Request: Add support for GLArea

[kiranandcode]

Not sure if this is the most elegant way of doing this, or even just correct, but it would be nice to have some support for GTK's GLArea class.

I've put something together based on the orphaned code in src-unsupported that allows adding a GLArea to an existing widget, but I'm not familiar with the API generation tools to work out what would be the correct way to provide full support for all the signals of the GLArea

[garrigue]

Sorry not to have reacted to this. Is this code working ? What is missing to run other examples ?