add a tuto item

tuto/lesson5/some.pat

+% What are the upos for a given word
+% The pattern below searches for the form "some"
+% The clustering key N.upos returns a clustering of the results for each possible upos of the N node
+
+pattern { N [form="some"] }
\ No newline at end of file

tuto/right_pane.html

@@ -67,6 +67,7 @@
   <div class="tab-pane" id="step5">
     <h4>Lesson 5: clustering of the results</h4>
     <ul>
+      <li><a href="#" clustering="N.upos" snippet-file="lesson5/some.pat" class="inter">Cluster by "upos" for a given form</a></li>
       <li><a href="#" clustering="GOV.upos" snippet-file="lesson5/upos.pat" class="inter">Cluster results by one node "upos"</a></li>
       <li><a href="#" clustering="N.lemma" snippet-file="lesson5/lemma.pat" class="inter">Cluster results by one node "lemma"</a></li>
       <li><a href="#" clustering="N.VerbForm" snippet-file="lesson5/verbform.pat" class="inter">Other clustering on nodes</a></li>