title: Check if RecyclerView is scrollable
body: <p>How to check if a <code>RecyclerView</code> is scrollable, ie, there are items below/above the visible area</p>
  
  <p>I have a dropdown in my recycler view which works by using <code>notifyItemRangeInserted()</code> and <code>notifyItemRangeRemoved()</code>. Whenever any of this happens, I want to check if the <code>RecyclerView</code> is scrollable or not, as I have to adjust another view, a banner like in newsstand, accordingly</p>