#206 Bound states for "ket" objects

[Burkhard Schmidt]

• Generalize qm_bound such as to run not only with "wave" objects but also with "ket" objects.
• Generalize qm_bound to treat also (constant!) external fields interacting with dipoles and/or polarizabilities

[Burkhard Schmidt]

To begin with, H0 will change from a vector (diagonal entries) to a (symmetric) matrix. Full or sparse