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Added some options for secure cloud/backup services :)
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Update README.md

Added VestaCP, GitLab, Observium, and Pritunl
Add NLNet Unbound to the list of DNS software

Unbound is just so dang good.
Added Opsview
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DRBD

Added DRBD to the list
rsnapshot

added rsnapshot to the list
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Added OpenDJ to LDAP Servers
Added Eclipse to Editors
Added SoftEther to VPN Servers
Added Naemon to Monitoring software
Added Sensu to Monitoring software
Added Thruk to Monitoring software
Added Shinken to Monitoring software
Added check_mk to Monitoring software
Add LibreNMS
Add SafeKeep
Add tinc