Merge pull request #452 from jimi1283/miscimprovements

Added distro signature for Ubuntu 13.04 raring
Modification to pre_install_network_config to work with esxcfg-nics
Merge pull request #453 from jimi1283/esxi_improvements

Modification to pre_install_network_config to work with esxcfg-nics
Merge pull request #454 from jimi1283/miscimprovements

Adding {g,i}PXE boot loaders to those being copied for tftp