Enhance and fix WPS UI

- Fixes WPS usage for open network
- Exposes WPS on UI for easy access to push button and pin based techniques
- Adds support for cancelling WPS
- Adds a dialog that reports a progress since WPS can take quite a bit of time
to complete

The WpsDialog code is enhanced from contribution by yoshihiko.ikenaga@jp.sony.com
on partner source.

Change-Id: Ib0103507e0192e8195e7bfeb1c8e8855c20e23ca