Catching exception on initial read_state
More specific error handling if domain not found

- Adding error codes from libvirt (rubified from
  http://libvirt.org/html/libvirt-virterror.html#virErrorNumber)
- Removing unnecessary check for nil server
referencing source of error codes
removing pry call
Merge branch 'read_state_fix' of github.com:keitwb/vagrant-libvirt

Conflicts:
	lib/vagrant-libvirt/action/read_state.rb