Misleading docs about matrix divison

Quoting from the [docs](https://nalgebra.org/docs/user_guide/vectors_and_matrices/#matrix-operations):

> Multiplication and division requires the matrix on the left-hand-side to have as many columns as the number of rows of the matrix on the right-hand-side.

This is not true for division: only division by a scalar is supported, or alternatively component-wise with `.component_div`.