Android: Update mobile and TV to use game covers

Using covers should give a consistent look to dolphin's library.

Source/Android/app/src/main/res/values/strings.xml

@@ -135,6 +135,7 @@
     <string name="wiimote_speaker_description">Enable sound output through the speaker on a real Wiimote (DolphinBar required).</string>
     <string name="audio_stretch">Audio Stretching</string>
     <string name="audio_stretch_description">Stretches audio to reduce stuttering. Increases latency.</string>
+    <string name="gametdb_thanks">Thanks to GameTDB.com for providing GameCube and Wii covers!</string>
 
     <!-- Interface Preference Fragment -->
     <string name="interface_submenu">Interface</string>