Adding EPEL, Simplevisor & Additional Zabbix Servs

* Include EPEL as part of the Dockerfile.
* Migrated to
[Simplevisor](https://simplevisor.readthedocs.org/en/latest/) as the
means to startup the services.
* Integrated Zabbix Java Gateway and the Zabbix Agent as well.
* Enable passwordless SSH Access.

[ticket: X]: ?
Merge branch 'release/0.1'