Fixes https://github.com/twentyhq/core-team-issues/issues/1432
We still have some follow-up issues here, I only took care of making the
essential of the table work, but the follow-up issues will be better
tackled after everything has been switched to div, otherwise we might
fix them multiple times.
A first round of refactoring of z-index has been made in a common
constant, where it is easier to understand, for which case, what should
be the order of the different layers.
Though we still need to have another round of refactor because of the
stacking contexts, mainly because of the header row that is creating a
stacking context that makes it hard to have all scrolling cases work.
Lucas Bordeau
821ae7c60d