Add omitted reduce signatures to synopsis

Author: jaredhoberock

algorithms.html

@@ -508,11 +508,24 @@ <h1>Header <code>&lt;experimental/numeric&gt;</code> synopsis</h1>
   template&lt;class InputIterator&gt;
     typename iterator_traits&lt;InputIterator&gt;::value_type
       reduce(InputIterator first, InputIterator last);
+  <ins>template&lt;class ExecutionPolicy,
+           InputIterator&gt;
+    typename iterator_traits&lt;InputIterator&gt;::value_type
+      reduce(ExecutionPolicy&amp;&amp; exec,
+             InputIterator first, InputIterator last);</ins>
   template&lt;class InputIterator, class T&gt;
-    T reduce(InputIterator first, InputIterator last<ins>,</ins> T init);
+    T reduce(InputIterator first, InputIterator last, T init);
+  <ins>template&lt;class ExecutionPolicy,
+           class InputIterator, class T&gt;
+    T reduce(ExecutionPolicy&amp;&amp; exec,
+             InputIterator first, InputIterator last, T init);</ins>
   template&lt;class InputIterator, class T, class BinaryOperation&gt;
     T reduce(InputIterator first, InputIterator last, T init,
              BinaryOperation binary_op);
+  <ins>template&lt;class ExecutionPolicy, class InputIterator, class T, class BinaryOperation&gt;
+    T reduce(ExecutionPolicy&amp;&amp; exec,
+             InputIterator first, InputIterator last, T init,
+             BinaryOperation binary_op);</ins>
 
   template&lt;class InputIterator, class OutputIterator,
            class T&gt;