GUI -- Added UiViewHidden subclass of UiView to allow for views that do not have an entry in the navigation panel.
- Added placeholder "flow" view.

Change-Id: I3a969d16baf608b132c10cfc7f154d0ce51c765e
diff --git a/web/gui/src/main/webapp/app/view/flow/flow.html b/web/gui/src/main/webapp/app/view/flow/flow.html
new file mode 100644
index 0000000..9c1de12
--- /dev/null
+++ b/web/gui/src/main/webapp/app/view/flow/flow.html
@@ -0,0 +1,4 @@
+<!-- Host partial HTML -->
+<div id="ov-flow">
+ <h1> Flows are here </h1>
+</div>