BUG: Do not return SmartPointers in TimeVaryingVelocityFieldTransform

All Get methods should return raw points.  This was detected by wrapping
warning about the SmartPointer's not being wrapped, ITK-3276.

Change-Id: Ied1ed4d705361551c20bc52f728dc81dbeba9a65
Merge topic 'GetTimeVaryingVelocitySmartPointer_release'

7c3a15eb BUG: Do not return SmartPointers in TimeVaryingVelocityFieldTransform