Relevant upgraders should be reincluded as constraints.

In case catalog and zodb is at a inconsistent state (after a backup restauration for example), this alarm can check if all security uids are well indexed.

Once a interaction is trigger after _setPredecessor don't propagate reindexation to invalidated software Instances.

i.e no single line of code in this entire repository can start supervisord implicitely if option is set.
In such case, the only way to start supervisord is to run slapos node supervisord explicitely.

Also do not autorestart.

Also move and simplify management of configuration files.

* based on rev 16a14ce of https://github.com/buildout/buildout/blob/1/bootstrap/bootstrap.py .
* update setuptools_source url to use the latest ez_setup.py so that the newest setuptools is used.

This reverts commit acc65d77.

Also fill missing changelog.