[functions.interfaces] return const shared_ptr& instead of shared_ptr
[functions.default] update
[functions.interface] updated report()
[functions.interfaces] added alpha() and gamma()
[functions.interfaces] added with_mu()
[la.container] added bindings for valid()
[core.bindings] do not expose data on EigenDenseVector

The resulting numpy array showed scrambled memory.
[core.bindings] added std::vector< EigenDenseVector >
[discretizations] added sanity check to bindings of MS discretization