fix gcc9 warnings

fix gcc9 warnings:

• Vertex had an explicit copy constructor, but not an explicit operator=. Remove copy constructor, and rely on the implicitly compiler generated version instead.
• AuxFunBase is a virtual base class, so remove the move constructor and move assignment, as in case of multiple inheritance the AuxFunBase move constructor/assignment may be called more than once for a given instance, which would lead to a move from an already moved-from state.