* New Strigi configuration: The nepomuk server can now read and write the strigi config directly.

This is necessary anyway since strigi does not support the command line parameters we used before anymore.

* Configuration GUI for Strigi exclude filters.
* Better Strigi runtime control including termination which is needed since Strigi does not care much about being exited during indexing.
* Using Soprano's new SignalFilterModel (if available) to restrict the number of updates in libnepomuk.