Conflicts:
	component/mariadb/buildout.cfg
	component/stunnel/buildout.cfg
	slapos/recipe/mysql/template/my.cnf.in

in pbs recipe.

This allow to update pbs section each time new slave instance
is added.

This try to swallow as much as possible slave instance bad requests.

oqgraph will be automatically built when libboost is available. In order to
follow separation from operating system avoid to building this not needed engine
and thus do not depend on operating system's library.

I updated the dropbear url because it wasn't uploaded to network cache.
I kept an old version because :
 * our patches don't work anymore with the latest version.
 * the latest version (at the date of this commit, doesn't have an
   interesting changelog).
 * by laziness.

I updated the dropbear url because it wasn't uploaded to network cache.
I kept an old version because :
 * our patches don't work anymore with the latest version.
 * the latest version (at the date of this commit, doesn't have an
   interesting changelog).
 * by laziness.