add popup section (copy text via JavaScript) in /user/storage.html.

This is just the HTML and CSS additions to the HTML template. The JavaScript has
not be implemented yet.

templates/user/storage.html

@@ -59,6 +59,20 @@
 	        <img alt="{{entry.title}}"
 	             src="/images/icons/view-entry.png">
             </a>
+            <div class="be-popup-container">
+                <span class="be-popup"
+                      id="{{item.slug}}-popup">
+                    Copied
+                </span>
+            <button class="be-gui-button-no-text"
+                    onclick="copyToClipBoard('{{item.slug}}')"
+                    data="{{item.slug}}"
+	            title="Copy URL for '{{item.name}}' to clipboard"
+	            type="submit">
+	        <img alt="Copy to clipboard"
+	             src="/images/icons/copy.png">
+            </button>
+            </div>
             {% if roles.administrator %}
             <form class="be-storage-rename"
 	          action="/storage/rename/{{item.slug}}"