Demonstrate password rotations using docker stacks/containers

[pkopriv2]

As a user, I'd like to be able to regularly rotate passwords, so that I can focus on other issues.

AC:

• Be able to securely change a password in an existing docker stack file.
• Be able to securely deliver the new stack file to a swarm
• Be able to securely change a password in a generic data file
• Be able to deliver the passwords via environment variables

Notes:

• This may include demonstrating password changes in remote systems (ie databases) so we can show the complete workflow.

[benhammes]

Done, but still needs documentation.

[benhammes]

Preston will send Mike a follow up email today. 8/7

[pkopriv2]