add/set ICAO and logo for airlines

database/migrations/2017_06_08_191703_create_airlines_table.php

@@ -15,10 +15,11 @@ class CreateAirlinesTable extends Migration
     {
         Schema::create('airlines', function (Blueprint $table) {
             $table->increments('id');
-            $table->string('code', 5);
+            $table->string('icao', 5);
             $table->string('iata', 3)->nullable();
             $table->string('name', 50);
             $table->string('country', 2)->nullable();
+            $table->string('logo', 255)->nullable();
             $table->boolean('active');
             $table->timestamps();