Adding switch to toggle Memory Overlay

-> The overlay causes performance regressions so it's hard to evaluate
   performance with it on.
-> Also, the WeightWatcher is still running regardless, so you can
   always check it
-> Saved as a shared pref

Change-Id: Iad5ccbeca2c2b4e0ec86294879f3eb09caa594e9
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 09a94ae..b9f75cf 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -96,6 +96,17 @@
         </activity>
 
         <activity
+            android:name="com.android.launcher3.ToggleWeightWatcher"
+            android:label="@string/toggle_weight_watcher"
+            android:icon="@mipmap/ic_launcher_home">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+
+        <activity
             android:name="com.android.launcher3.WallpaperChooser"
             android:theme="@style/Theme.WallpaperPicker"
             android:label="@string/pick_wallpaper"