Final aws3 changes into master

This version included below updates..
    - Allow single AZ support for dataReplica=1 selection, where single AZ will be used for cluster with 1NAT device and 1 privateSubnet but still user need to enter 2 AZ in AvailabilityZones.
    - Re-factorization of existing code where whole ec2-tools would be replace by smcli commands.
    - Some cosmetics changes included like internal template versioning to differentiate two templates releases.
    - Included some more internal logic to add failure group 3 and descriptor should be distributed properly.
    - Added SSM to handle SSH keys, which remove ssh keys dependencies with S3 bucket.
    - Added some cosmetic changes.

Author: dheren-git