There were isssues with ghosting and invalid image bounds due to
vtkResampledAMRImageSource ending up using partial bounds from an AMR being
delieved part of the streaming process. This fixes that.

Also vtkAMRStreamingPriorityQueue can now discard blocks that are totally
outside given bounds.

Change-Id: I14f15f380864d87c787d23a7eeff21a8a6415884