Made PolicyLearningLossVisitor to also work with multidimensional datasets

Author: hosseinmoein

docs/HTML/DataFrame.html

@@ -2059,6 +2059,10 @@ <H2 ID="2"><font color="blue">API Reference with code samples <font size="+4">&#
       <td title="Pattern types"><a href="https://hosseinmoein.github.io/DataFrame/docs/HTML/pattern_spec.html">pattern_spec</a>{}</td>
     </tr>
 
+    <tr class="item" onmouseover="this.style.backgroundColor='#ffff66';" onmouseout="this.style.backgroundColor='#d4e3e5';">
+      <td title="Specifies the baseline/normalization for policy gradient loss"><a href="https://hosseinmoein.github.io/DataFrame/docs/HTML/PolicyLearningLossVisitor.html">policy_loss_baseline</a>{}</td>
+    </tr>
+
     <tr class="item" onmouseover="this.style.backgroundColor='#ffff66';" onmouseout="this.style.backgroundColor='#d4e3e5';">
       <td title="Specifies the methods to generate probability distribution"><a href="https://hosseinmoein.github.io/DataFrame/docs/HTML/NormalizeVisitor.html">prob_dist_type</a>{}</td>
     </tr>