add git branch -v explanation

branching/index.html

@@ -215,6 +215,21 @@ Deleted branch testing (was 78b2670).
 * <span class="green">master</span>
 </pre>
 
+    <h4>
+      git branch -v
+      <small>see the last commit on each branch</small>
+    </h4>
+
+    <p>If we want to see last commits on each branch 
+    we can run <code>git branch -v</code> to see them.</p>
+
+<pre>
+<b>$ git branch -v</b>
+* <span class="green">master</span>      54b417d fix javascript issue
+  development 74c111d modify component.json file
+  testing     62a557a update test scripts
+</pre>
+
     <h4>
       git push (remote-name) :(branchname)
       <small>delete a remote branch</small>