Main Activity Fragments should be updated automatically now when the Media Store has changed.

app/src/main/java/com/kabouzeid/gramophone/interfaces/MusicStateListener.java

@@ -0,0 +1,14 @@
+package com.kabouzeid.gramophone.interfaces;
+
+/**
+ * @author Karim Abou Zeid (kabouzeid)
+ */
+public interface MusicStateListener {
+    void onPlayingMetaChanged();
+
+
+    void onPlayStateChanged();
+
+
+    void onMediaStoreChanged();
+}