Merge remote-tracking branch 'firebase/version-2.0.0-dev' into non-critical-#544

# Conflicts:
#	database/src/main/java/com/firebase/ui/database/FirebaseRecyclerAdapter.java

Author: SUPERCILEX

database/src/main/java/com/firebase/ui/database/FirebaseRecyclerAdapter.java

@@ -137,12 +137,6 @@ public int getItemCount() {
         return mSnapshots.size();
     }
 
-    @Override
-    public long getItemId(int position) {
-        // http://stackoverflow.com/questions/5100071/whats-the-purpose-of-item-ids-in-android-listview-adapter
-        return mSnapshots.get(position).getKey().hashCode();
-    }
-
     @Override
     public VH onCreateViewHolder(ViewGroup parent, int viewType) {
         View view = LayoutInflater.from(parent.getContext()).inflate(viewType, parent, false);