Add "Notes" to Airports (#1467)

* Notes for Airports

Adds capability of having notes/remarks for airports, includes

* New database field
* Airport Model change
* CSV Import/Export capability for notes
* Admin Airports list page change
* Admin Airports edit page change
* Default Template Airport show page change

* Update Airport Tests

* Add the new field to source csv
* Check if the import works

* Update AirportFactory.php

Co-authored-by: Nabeel S <nabeelio@users.noreply.github.com>

tests/ImporterTest.php

@@ -670,6 +670,7 @@ class ImporterTest extends TestCase
         $this->assertEquals('-97.6699', $airport->lon);
         $this->assertEquals(0.0, $airport->ground_handling_cost);
         $this->assertEquals(setting('airports.default_jet_a_fuel_cost'), $airport->fuel_jeta_cost);
+        $this->assertEquals('Test Note', $airport->notes);
 
         // See if it imported
         $airport = Airport::where([