added vc_vpxsettings type / provider

removed autorequire coments
Merge pull request #88 from sholland/tb/vpxsettings

added vc_vpxsettings type / provider
ESX Maintenance Mode

Ensurable puppet resources that supports:
- entering MM
  - optional timeout (defaults to no timeout)
  - optional evacuation of powered off VMs, requires virtual center
- exiting MM
  - optional timeout (defaults to no timeout)
Merge pull request #94 from dscherer/maintenance_mode

Maintenance mode