Bug fix to initiator annihilation for multiple particle types.
Bug fix to initiator annihilation for multiple particle types.

We were not taking into account a determinant might be already occupied
by only some particle types.  If a determinant is not already occupied
by a given particle type then usual initiator rules must apply.

hande-qmc/hande,hande-qmc/hande,hande-qmc/hande,ruthfranklin/hande,hande-qmc/hande,hande-qmc/hande