[Development] Example clean-up for Qt 5

[Sorvig Morten]

>Help by offering your opinion on:
>* Does the example have a meaningful purpose? Or is the feature it demonstrates deprecated or obsolete in Qt 5?
>* Does it follow Qt 5 "best practice" / recommended way of doing things?
>* Are the comments, text strings, README, etc up to date?
>* Is the example documentation, i.e. the corresponding .qdoc file, if any, up to date?
*> Does the structure follow the example shown here: http://qt-project.org/wiki/Qt_Documentation_Structure ?

One thing which I'd like to do, and which is perhaps out of scope for this project, is to find a different mechanism for the documentation tags ("//! [1]" etc). In my highly subjective opinion this uglifies the examples to much and is not how we want to present clean, simple, Qt code.

- Morten