Added d3 force graph to GUI2 topology

Change-Id: I6860472efaf51ea27fad74e630e687f0c6abad3d
diff --git a/web/gui2/src/main/webapp/app/view/topology/layer/nodeviceconnectedsvg/nodeviceconnectedsvg.component.html b/web/gui2/src/main/webapp/app/view/topology/layer/nodeviceconnectedsvg/nodeviceconnectedsvg.component.html
index d201c8a..9233713 100644
--- a/web/gui2/src/main/webapp/app/view/topology/layer/nodeviceconnectedsvg/nodeviceconnectedsvg.component.html
+++ b/web/gui2/src/main/webapp/app/view/topology/layer/nodeviceconnectedsvg/nodeviceconnectedsvg.component.html
@@ -13,7 +13,7 @@
 ~ See the License for the specific language governing permissions and
 ~ limitations under the License.
 -->
-<svg:g id="topo-noDevsLayer" transform="translate(500,500)" style="visibility: visible;">
+<svg:g xmlns:svg="http://www.w3.org/2000/svg" id="topo-noDevsLayer" transform="translate(500,500)" style="visibility: visible;">
     <svg:g id="reposition" #reposition [attr.transform]="centre(reposition.getBBox())">
         <svg:use width="100" height="100" class="noDevsBird" href="#bird"></svg:use>
         <svg:text x="120" y="80">No Devices Are Connected</svg:text>