Simplifies editing the software release by removing the need to edit
instance-erp5-cluster.cf.in each time.
Applied to kumofs, cloudooo, mariadb and zodb.
Partially applied to frontend, as it is more complex.
Not applied to zope, as it is even more complex - but also topical to this
software release.
Also, change default timezone to UTC, to be neutral.
Also, reformat section extension.

Also, replace cloudooo-json by exposing its internals directly.

This work has nothing to do in erp5-component branch, and is preventing it
from being merged to erp5 banch more often.
Conflicts because of non-reverted
6d1a9805 have been resolved to that its
intent is preserved with non-cluster ERP5 SR.

This reverts commit 77976a14.
This reverts commit 7aa1d92c.
This reverts commit 80062015.
This reverts commit 36ed58f2.
This reverts commit 1fe3f466.
This reverts commit 7731726a.
This reverts commit eb2016c4.

All ERP5 profile is now in a single place.
Moreover, use slapos.cfg stack.