RemoteViewsTarget feature requested on #242

Ability to load a bitmap into an ImageView of a Widget using
RemoteViews.

Example of usage on the following gist
https://gist.github.com/pavlospt/00242d5102ac8f76e169
Sorry I meant to emphasize the ``Bitmap`` part. Instead of using the generic Z parameter (ie ``xxx extends SimpleTarget<Z>``, you should just use Bitmap directly (ie ``xxx extends SimpleTarget<Bitmap``) because that's the only resource type these Targets actually support.