They are concepts that are not really necessary with local
storage, that I do not really want to explain to other people.

Only register generators globally. This makes inspection of cache
items much easier.

This reverts commit e1bbce4c.

for style reasons

The driver solves the PDE given by the first form in forms. This is a
first step towards instationary problems.

It allows the sorting of preambles having different
cache item type.

The driver solves the PDE given by the first form in forms. This is a
first step towards instationary problems.

This reverts commit d0a87348.