qml controls and documentation

[David Edmundson]

All fixed!

Some important notes:

QtDoc changes will be in 5.4. I can just upload my generated .tags
file to the api.k.o server in the meantime.

It requires explicitly stating inheritance in documentation
i.e

/**
   @class Text
   @short A text label styled using the plasma theme fonts and colours
   @inherit QtQuick.Text
*/
Text {

}

I wrote automatic @inherit resolving into doxyqml, but it doesn't work
where there is no module explicitly set (i.e "import QtQuick 2.0" vs
"import QtQuick 2.0 as Cheese").