Added to config UI drone display list: getDronesListButton to connect to DB and retreive drones list and dronesListComboBox to display drones list.
In ConfigurationPanel, cmdP previously variable in on_nextButton_clicked() is now a member of ConfigurationPanel. All db configuration checkng operations have been moved to on_getDronesListButton_clicked().
Added open db in ConfigurationPanel and error msg if cannot open.
Added default void selection for drones in configuration panel.
Added to ConfigurationPanel retreiving drone list from db and displaying in dronesListComboBox.
Check that a drone is selected in configuration panel before validating form.