Avoid creating new remote and beamer instances in onCreate()

app/src/main/java/eu/worn/apps/androvac/MainActivity.java

@@ -44,14 +44,17 @@ public class MainActivity extends AppCompatActivity implements View.OnClickListe
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
 
-        remote = new RoboVac11sRemote();
+        if (remote == null)
+            remote = new RoboVac11sRemote();
 
-        beamer = new AndroidIRBeamer(this);
-        if (!beamer.isAvailable()) {
-            Toast.makeText(this.getApplicationContext(),
-                    "No IR beamer found: entering debug mode",
-                    Toast.LENGTH_LONG).show();
-            beamer = new DebugIRBeamer(this);
+        if (beamer == null) {
+            beamer = new AndroidIRBeamer(this);
+            if (!beamer.isAvailable()) {
+                Toast.makeText(this.getApplicationContext(),
+                        "No IR beamer found: entering debug mode",
+                        Toast.LENGTH_LONG).show();
+                beamer = new DebugIRBeamer(this);
+            }
         }
 
         findViewById(R.id.schedule).setEnabled(