- added assertions on frmcell, frmminorstrata, frmvessel, frmvesseltype, to assure that we don't have an empty combo box (this should be prevented by the model rules!);
- moved validation of selected frame to the rules on the database (frmframe);
- removed translation call from sql field (frmvesseltype);
- refactored query to filter values on the vesseltype combo (frmvesseltype);
- removed obsoloete function initmapper1 (frmvesseltype);