Port core to PowerPC for BlueGene/Q purposes

1. Fix a few missing includes.
2. Add an OTHER_BLAS define so that we can optionally skip blas.
3. Define 'accelerate' external only on Mac.
4. Fix stability of Cylinder::normal and surface.
5. Make MovWriter and OpenMesh tests disappear if support is disabled.
6. Fix .npy and .try I/O for big endian.
7. Make Random123 allow powerpc.