[Nepomuk] Nepomukcontroller rewritten in QML

[Jörg Ehrichs]

>
> Is it ready to give it another review?
>

Yes it is, but please have a look at the nepomukcontroller-qml branch
in kde-workspace as this is the codebase I like to git merge in about
2 weeks if no one is against it.

The code base is the same as in my scratch repo, but the cmake part
is a bit different to be able to build it together with the rest of
kde-workspace.