The Plastik decoration buttons are provided by a declarative
extension plugin as the canvas drawing API would be needed to
draw these buttons. This should be changed with Qt 5.
But it's also a nice example to show how a QML based decoration
can have an extension in C++.
This theme engine uses SVG files to theme the decoration like the themes for Plasma desktop shell.
svn path=/trunk/playground/artwork/aurorae/; revision=983819