Add subnet selection to ec2 nested stack
Add subnet selection to ec2 nested stack

This provides the capaability to place nodes in a specific availibility zone

tinnightcap/nubis-stacks,gozer/nubis-stacks,limed/nubis-stacks,Nubisproject/nubis-stacks,limed/nubis-stacks,Nubisproject/nubis-stacks,gozer/nubis-stacks,tinnightcap/nubis-stacks