Support shrink-to-fit.

This patch does;
* add the item ShrinkToFitResize to the KoTextDocument::ResizeMethod enum
* loads the draw:fit-to-size bool (chapter 19.121 in ODF 1.2) and sets the resizeMethod to ShrinkToFitResize if true
* implements the fitToSize-method to shrink the content in a textshape to fit into the shape's boundaries

That is done by implementing the TextViewConverter decorator that adjusts a KoViewConverter with the shrink-to-fit (and maybe in the future other) values transparently.

Compared to using painter.scale direct this should provide us more flexibility, cleaner code and a clear separation.