title: get part of std::tuple
body: <p>I have a tuple of unknown size (it's template parametr of method)</p>
  
  <p>Is it way to get part of it (I need throw away first element of it)</p>
  
  <p>For example, I have <code>tuple&lt;int,int,int&gt;(7,12,42)</code>. I want <code>tuple&lt;int,int&gt;(12,42)</code> here</p>