When looking for emergency user, zope configuration is not fully loaded
yet, thus if we do not set INSTANCE_HOME at startup, it will be wrong.
With this change, setting an "access" file under erp5shared folder will
work properly

In the same time, fix HOME folder to not be in a tmp folder

Add support for "hosts" aliasing in Zope instances.
Add support for SASL relayhost with mandatory TLS encryption.
Add mandatory TSL + SASL authentication, to not be an open relay.
Wrap postfix commands with proper environment instead of symlink +
source-able script.
Add ipv6 listening support (untested).
Drop non-required main.cf configuration options.
Make postifx instance optional (requires postmaster address to be
provided).
Document and rework smtp-related parameters.
Expose an userhosts hostname for smtp server.
Add diversion support (solution to "prod clone sent mails to real customer").
Use etc/run rather than etc/service, for consistency (if it needs to be
changed, it must be changed for all software types).
Hook into syslog and setup local syslog daemon, with logrotate integration.
Update TODO entries.

Extend m4 as it is not guaranteed to be pulled by other dependencies.
Call toochain commands with explicit path, and simplify PATH as a
result.

you can extend component/numpy/openblas.cfg to build numpy with OpenBLAS.

This reverts commit d48851e9.

Turns out, "logger" command (with which this tool was developped) is not
actually using libc's syslog API, so is not representative of proper
syslog usage. Also, syslog API happens to be extremely painful to hook
(500 lines of libc code to fork because of direct internal accesses,
constants and static globals).
Syslog hooking will happen someday, just not this way.

slapos.core.git moved to lab.nexedi.cn and repository on git.erp5.org
made readonly. Update all referenced to old repository location:

    http://git.erp5.org/repos/slapos.core.git

->

    https://lab.nexedi.cn/nexedi/slapos.core.git

/reviewed-by trustme

/reviewed-by: TrustMe

* lab/master:
  Add Ivan's certificate.
  use slapos.cookbook 1.0.9

Add Ivan's certificate.

Please accept so I can start upload to schacache for Wendelin release.

See merge request !16