feat: Show country selection on first app start

Sources/Earthquake Network/Controllers/Seismic Networks/SeismicNetworksViewController.swift

@@ -45,6 +45,13 @@ class SeismicNetworksViewController: EQNBaseViewController, UITableViewDelegate,
 
         setupUI()
         refreshUI()
+        
+        // only the first time, show the popup for country selection
+        let alreadyPresented = UserDefaults.standard.bool(forKey: EQNUserDefaultKeyOneShotShowCountry)
+        if !alreadyPresented {
+            performSegue(withIdentifier: Self.SegueIdentifierSettings, sender: nil)
+            UserDefaults.standard.setValue(true, forKey: EQNUserDefaultKeyOneShotShowCountry)
+        }
     }
     
     private func setupUI() {

Sources/Earthquake Network/Costanti.h

@@ -40,7 +40,7 @@ static NSString * const EQNServerUrlUploadSettings = @"https://srv.earthquakenet
 #pragma mark - UserDefaults Keys
 
 static NSString * const EQNUserDefaultKeySesmicInformations = @"EQNetwork.SeismicInformations";
-
+static NSString * const EQNUserDefaultKeyOneShotShowCountry = @"EQNetwork.OneShot.CountrySelection";
 
 // URL registrazione server
 #define URL_SERVER_REGISTRAZIONE @"http://srv.earthquakenetwork.it/distquake_upload_gcm_regid2.php"