convert App to kotlin

app/src/main/java/com/simplemobiletools/calendar/App.java

@@ -1,13 +0,0 @@
-package com.simplemobiletools.calendar;
-
-import android.app.Application;
-
-import com.facebook.stetho.Stetho;
-
-public class App extends Application {
-    @Override
-    public void onCreate() {
-        super.onCreate();
-        Stetho.initializeWithDefaults(this);
-    }
-}

app/src/main/kotlin/com/simplemobiletools/calendar/App.kt

@@ -0,0 +1,12 @@
+package com.simplemobiletools.calendar
+
+import android.app.Application
+
+import com.facebook.stetho.Stetho
+
+class App : Application() {
+    override fun onCreate() {
+        super.onCreate()
+        Stetho.initializeWithDefaults(this)
+    }
+}