Migrate AWS resources for Vietnam demo stack

[jeancochrane]

Checklist:

• For each of { database, app, celery } instances:
  • Create an AMI/snapshot and share with the new account (guide)
  • Launch instance in the new account
    • For the app server, attach an Elastic IP
  • Provision security groups following the firewalls in the Ansible config
• Once all instances are up, edit service definitions for each instance in /etc/init/*.conf to point to new hostnames/IPs
• Copy relevant Route53 DNS rules from the old account to the new one
• Remove Route53 DNS rule from the old account
• Test to see whether everything is wired up properly

Checklist may change depending on how the first migration goes. If steps need to be added or removed, update those issues accordingly.

Connects #739

See:

• Launching Linux instances from a backup
• How to Create a Custom AMI with Encrypted Amazon EBS Snapshots and Share It with Other Accounts and Regions (encryption may be unnecessary)