Added d3 force graph to GUI2 topology

Change-Id: I6860472efaf51ea27fad74e630e687f0c6abad3d
diff --git a/web/gui2/src/main/webapp/app/view/topology/layer/forcesvg/visuals/hostnodesvg/hostnodesvg.component.css b/web/gui2/src/main/webapp/app/view/topology/layer/forcesvg/visuals/hostnodesvg/hostnodesvg.component.css
new file mode 100644
index 0000000..60cedab
--- /dev/null
+++ b/web/gui2/src/main/webapp/app/view/topology/layer/forcesvg/visuals/hostnodesvg/hostnodesvg.component.css
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+/*
+ ONOS GUI -- Topology View (forces host visual) -- CSS file
+ */
\ No newline at end of file