erp5testnode is not fully stable yet, we often need to
update it, we don't need to fix everything right now
This reverts commit 7f251b0c.

This will allows to use it for several different external method
calls

As zabbix agentd cannot run in foreground mode wrap it in simple foreground
application which sends singals whenever it is requested to be killed.

Instantiation shall depend on minimal tools, like system administrator would.

Superseded by buildout:allow-hosts, was not functional anyway.