Updating this sample to show how Capabilities APIs can be used.

In addition, the sample has been modified to showcase different features
on different pages; the asset transfer api is now moved to its
own page and the new capabilities api is used in node discovery
and has its own page; there user can see a list of connected
watches separate from a list of connected phones.

Bug: 19502892
Change-Id: I57d6be68d2d9685d7c1d8c51f63a88092abaebcc