Update to version 19.1.0 of the Android Support Library.

Allows app to make use of the new SwipeRefreshLayout class in
the future.

Signed-off-by: Greg Meiste <greg.meiste@gmail.com>
Update to version 2.2.4 version for Google Gson library

Signed-off-by: Greg Meiste <greg.meiste@gmail.com>
Replace PullToRefresh with SwipeRefreshLayout

Use the library provided by Android in the support library. It is
not quite as nice, but it is standardized, and removes one more
dependency from PTW.

Signed-off-by: Greg Meiste <greg.meiste@gmail.com>