A pattern that we have been manually implementing in quite some places!

This is not used anymore since we have mixins.

In many places we treat this as codegen-time information anyway.
For loopy, this is the necessary way to go.

The Exadune preconditioners cant handle one sided assembly for reasons.

By looking at the possible values of the condition.

I have a case where visiting has a side effect that I want to avoid.
Also spares work.

This options enables to generate jacobian apply methods regardless
of the `matrix_free` option. If `matrix_free` is set to true,
`generate_jacobian_apply` is also set to true. This option replaces
`matrix_free` in all contexts except in the selection of the solver.