[Dillo-dev] form widgets, ascent/descent

I was playing around in dw, and noticed that, whereas form widgets normally like to put much of their height into descent, when style sets the height, Textblock::calcWidgetSize() puts it all into ascent. I checked firefox and saw that their form widgets ascend. If we made everything ascend and just put font->descent into the descent, it would make life simpler. Or, nearly. I guess there is RELIEF_Y_THICKNESS, but I could almost ignore that...