Complex and general MO 2ERIs

[leethomo86]

Extend code to deal with symmetry when complex 2ERIs used (2x2-fold symmetry instead of 8-fold symmetry). Develop code to compute GHF MO 2ERIs.

[leethomo86]

The first goal is to implement 2 and 4 fold symmetry for R4 tensors into MQC algebra routines. The second goal is to use the 4 fold symmetry in MQC EST 2ERI routines to account for complex conjugation symmetry. The third goal is to update the 2ERI transformation routine to be able to deal with GHF wavefunctions. Note that all non-zero blocks are currently stored to deal with different bra and ket reference orbitals, but routines can be modified to use symmetry when desired, or by default.

[leethomo86]

Code has been implemented to pass back the 16 spin combinations. However, only the (aa|aa), (aa|bb), (bb|aa) and (bb|bb) have been properly debugged and confirmed to be correct.

[leethomo86]

Remaining MO 2ERIs have been debugged and parallelized for generalized spin orbitals in commit #101