Fixed typo in arnoldi method.
Updated TriHeisenberg Hamiltonian to use new Model interface.
Added projector operators to Z3.
Added some fixes for m=1 case in SVD.
Added support for Observer to gateTEvol.
Added method psiphiC (better name?) for computing Complex wavefunction overlaps.
Fixed a very minor typo in HubbardChain Hamiltonian builder.
Fixed a problematic friend declaration in sparseref.h
Removed deprecated register keyword from MatrixRef code.
Added forward declarations for a couple of friend functions.