Added reboot check before attempting to provision

If the guest is shutting down don't start the chef provisioning run, wait for the machine to come back up in a ready to communicate state.

This solves the problem where chef provisioning may try to start while the machine is shutting down. Depending on the timing this can lead to the dna.json file not being found or at the very least requiring chef to try another attempt.

As a real world example this fixes our CI build of our VisualStudio cookbook that has 2 provisioning steps

1. Install .NET 4.5 & reboot
2. Install Visual Studio