CB-9374 Android: add SplashShowOnlyFirstTime as preference

Github: close #70

src/android/SplashScreen.java

@@ -89,7 +89,10 @@ public class SplashScreen extends CordovaPlugin {
         // Save initial orientation.
         orientation = cordova.getActivity().getResources().getConfiguration().orientation;
 
-        firstShow = false;
+        if (preferences.getBoolean("SplashShowOnlyFirstTime", true)) {
+            firstShow = false;
+        }
+
         loadSpinner();
         showSplashScreen(true);
     }