Transition to Open3D v0.15.1 and upgrade tests

[Algomorph]

• Open3D 0.15.1 changes method semantics for voxel grids -- hash block allocation is now (very appropriately) split out from Integrate method into a separate method in the TsdfVoxelGrid class. We need to do the analogous changes for IntegarateWarped in WarpableTsdfVoxelGrid.
• These changes will allow us to test the "warpable" allocation routines explicitly. Take advantage of this opportunity to do so -- use real image data for source frame and synthesize target frame as rotation & translation, with some extra information around the edges of the observed object.