[ONOS-3851] Add skeletal code of Web GUI for Control Plane Manager

Change-Id: I0df9c55daec0b6d9a630aa954808e6c310ba861c
diff --git a/apps/cpman/app/src/main/resources/gui/css.html b/apps/cpman/app/src/main/resources/gui/css.html
new file mode 100644
index 0000000..abc11f5
--- /dev/null
+++ b/apps/cpman/app/src/main/resources/gui/css.html
@@ -0,0 +1 @@
+<link rel="stylesheet" href="app/view/cpman/cpman.css">
\ No newline at end of file