Added options to draw PointPlacemark images and labels to PointPlacemarkAttributes.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@2381 822214bb-dcf7-4c8d-a767-17ae0fb20d88
Added transparent image needed by PointPlacemark when not drawing the normal or default image.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@2382 822214bb-dcf7-4c8d-a767-17ae0fb20d88
Added getter methods to OrderedPlacemark for placePoint and terrainPoint, per MDA-65.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@2383 822214bb-dcf7-4c8d-a767-17ae0fb20d88