message: Added docs for Hurst exponent
diff: @@ -488,7 +488,7 @@ table.hovertable td {
  <tr onmouseover="this.style.backgroundColor='#ffff66';" onmouseout="this.style.backgroundColor='#d4e3e5';">
  <td title="Sets the Spin Lock"><a href="https://htmlpreview.github.io/?https://github.com/hosseinmoein/DataFrame/blob/master/docs/HTML/remove_lock.html">set_lock</a>( )</td>
  <td></td>
  - <td></td>
  + <td title="Calculates Hurst exponent">struct <a href="https://htmlpreview.github.io/?https://github.com/hosseinmoein/DataFrame/blob/master/docs/HTML/HurstExponentVisitor.html">HurstExponentVisitor</a>{ }</td>
  <td></td>
  </tr>
  