Added Services interaction to return a list of Service URIs.

@@ -266,6 +266,21 @@
           
         </output>
       </operation>
+
+      <operation name="Services">
+        <comment>
+          Operation returns the list of calculation service URIs available.
+        </comment>
+        <input name="input" type="Tensor.InputBase"  sid="0x1062">
+        </input>
+        <output name="output" type="Tensor.OutputBase" sid="0x1063">
+          <elem name="uriServices" multiplicity = "0..*" type="Tensor.uri">
+              <comment>One or more services to use to process the specified data sets.   Analysis can comprise multiple services 
+              processing the datasets and producing reports that provide a comparative performance. 
+              </comment>
+          </elem>      
+        </output>
+      </operation>
     </interface>
 
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