Nexenta support
reworking the patch for the branch master.
putting install_profiles of nexenta into nfs, not tftp.
New template files needed for ESXi 6.0
Added ESXi 6.0 signature.
Minor changes to support ESXi 6.x distros.
Merge pull request #777 from jmaas/master

Fix manpage: server-override -> server
Merge pull request #774 from piousbox/master-nexenta

Nexenta support
Merge pull request #776 from sidrew/master

Template changes/additions and pxegen.py updates to support ESXi 6.x distros.