FieldAttribute: Bugfix: Error prevents saving (only) the 'fields' table of an edited field
FieldAttribute: Bugfix: Error prevents saving the 'fields' table if the field was created by the drawing tool (it has no f_id)
FieldAttribute: Bugfix: The field drawing tool ('DigitalizeFieldCursorTool') misses the properties file for lable names ('de_DE.properties')