* added focus proxy
* using &QLineEdit::editingFinished as signal (changes value also when focus is lost)
* use enum to set how values are displayed
* search for DB values by leveraging the smart selector functions
* added isSet functions
* minor renamings/formatting
* embedded in form
* rectified readOnly / only for selection
* added uper case validator where missing
* selecting airline triggers loading of default livery
* renamed to connectDataReadSignal
* removed unused individual signals, e.g. vatsimMetarsRead -> replace by data read signal + entity flag
* added data in METAR class (kept there, not in airspace monitor) -> reader aware