Adding 'snippet' tab to parameter datatype signature UI

This new section displays how a complex datatype should look like providing some sample code for the developer using Swagger.

src/main/template/signature.handlebars

@@ -0,0 +1,18 @@
+<div>
+<ul class="signature-nav">
+    <li><a class="description-link" href="#">Description</a></li>
+    <li><a class="snippet-link" href="#">Snippet</a></li>
+</ul>
+<div>
+
+<div class="signature-container">
+    <div class="description">
+        {{{signature}}}
+    </div>
+
+    <div class="snippet">
+        <pre>{{{sampleJSON}}}</pre>
+        <small>Click to set as parameter value</small>
+    </div>
+</div>
+