Add a separate dialog for the password prompt

The user might be queried for the password during the connect stage
if no password was previously provided. Add a separate dialog for
this rather than abusing the connect dialog.

vnc.html

@@ -185,6 +185,16 @@
 
     </div> <!-- End of noVNC_control_bar -->
 
+    <!-- Password Dialog -->
+    <div class="noVNC_center">
+    <div id="noVNC_password_dlg" class="noVNC_panel">
+        <ul>
+            <li><label><strong>Password: </strong><input id="noVNC_password_input" type="password" /></label></li>
+            <li><input id="noVNC_password_button" type="button" value="Send Password" class="noVNC_submit" /></li>
+        </ul>
+    </div>
+    </div>
+
     <div id="noVNC_container">
         <h1 id="noVNC_logo"><span>no</span><br />VNC</h1>