Multiple changes, mostly in GUI and serializaton

1. Changes in Decision lib:
1.1 Bugfixes in QDataStream serialization
1.2 Add QDebug output
1.3 Add operator== for Decision and PropertiesGroup
1.4 Fixes in PropertiesGroupCreator - previously rank was intialized
with random value, which leads to incorrect PropertiesGroup.
1.5 TargetResources for Decision are now correctly determineg ( well,
at least blank resources aren't now being added anymore )

2. Changes in DDMS
2.1 Fix bug in service when Decision wasn't written to file
2.2 Fix bugs in SQL queries.

3. Changes in GUI.
3.1 QML is at least detecting resources
3.2 Remove KUrlRequester as unsufficent. Replace with custom dialog with
Nepomuk::SearchWidget for selecting resources