fixes #7297 - corrected name of DNS namespace in virsh error handlers

Refactored DNS and DHCP specifics back into the respective modules
Fixes #7438: moved facter loading into the facter plugin descriptor
fixes #7596 - validate plugin dependencies when loading, various fixes
Fixes #7181: added initial support for rubocop
Fixes #7749 - allow using logger in log_halt helper
fixes #7850 - pin mixlib-shellout for Ruby 1.8 compatibility
fixes #7822 - forbid HTTPS requests with no client SSL certificate
Fixes #7860 - added puppetssh_wait option
Fixes #7862 - Upgrade rubocop version