fix(machineidentity): add nocloud to ignored data sources

https://github.com/racker/cloud-init/blob/master/cloudinit/sources/DataSourceNoCloud.py#L46-L50
https://github.com/racker/cloud-init/blob/master/cloudinit/sources/DataSourceNone.py#L40-L41
Merge pull request #128 from virgo-agent-toolkit/fixes/add_nocloud

fix(machineidentity): add nocloud to ignored data sources