Large rework unifying hamiltonian application for linear and cubic

Introducing a new local_operator type, it is possible to unify the hamiltonian application between cubic and linear.

The only routine that remains doing the job is FullHamiltonianApplication(). It is taking care, depending on the job to start communications before running calculations.

This is a major rework of the code. @luigigenovese, we can discuss about it in 8 days after I'm back from holidays.