ENH: Adjustments to test images (reduced size) to increase test speed.

ENH: Updated AtlasBuilderUsingIntensity test data.
ENH: Updated TransferLabelsToRegions SPL label map to use compression.

Change-Id: I73fdb162e44f8570be3ed4077b936ba270cf5db8
Merge topic 'rk-ImageSizeForTestsAdjustments'

08b6a43 ENH: Adjustments to test images (reduced size) to increase test speed.