request: Prepare support for plain python list options.
Make all erp5_promise recipe options optional.

Also, reduce code duplication.
Bump zc.buildout egg version.
Make tidstorage-repozo arguments more readable.

Split line more naturally (don't separate switch from related argument).
Use long options instead of abbreviations.
Accelerate repozo by loosening checks.

Loosened checks are considered safe enough, and the speedup on many-GB
FileStorage files is significant.
Make ERP5 SR able to deploy an ERP5 cluster.
Add a mysql_tzinfo_to_sql wrapper for mariadb and remove --no-default param

vincent: Minor fixes. Move branch switch to a separate commit.
vincent: Provide configuration to mysql_install_binary.
Use a boolean rather than using an integer as a boolean.

Also, follow naming convention.
Avoid reusing local for different purposes.
Ignore case in storage families.

This value is used as a directory name, so we should follow the common
denominator.
use-ipv6 is a partition parameter, not a template parameter.
Make my.cnf.in parameters mandatory.

Better failing than silently ignoring a missing parameter because of a
typo. Only parameters provided by users should be allowed to be missing,
not internal ones.
Fix my.cnf.in parameter type.
Add an XXX about slapos rule being ignored by a cloudooo parameter.
Define parameters using a json schema.
Add minimal support for NEO-backed storage.

Only able to use a pre-existing NEO cluster.
Fix my.cnf typo in parameter name.
Get rid of unused/unsupported software type.

Drop instance-erp5-single and instance-zope:
All deployments of ERP5 instances must be covered by cluster-style
deployment, and tweaked by parameters rather than software type.
Drop instance-varnish:
This is not used currently, so avoid giving the impression that it is
supported. Revive when properly integrated.
Get rid of single/cluster distinction last traces.
Enable zeo backups by default, to be consistent with mariadb.