Vector-Vector binary operators should return Vector instead of Matrix

[calcmogul]

Vector inherits its binary operators from Matrix, which return a Matrix if the right-hand side is a Vector. It should return a Vector instead.

Vector should provide two overloads for each binary operator where the Vector RHS overload returns Vector and the Matrix RHS overload returns Matrix. The Matrix RHS overload might already be implicitly provided by the base class, so Vector itself just needs the more specific Vector RHS overload.