ESC Adoption Guide: Moving from secrets and config in stack files to ESC

[jkodroff]

Write an adoption guide to help customers adopt ESC for their configuration and secrets:

• Use an example of a simple stack that requires a plaintext value for config and a secret, e.g. a DB connection string. Launching a simple containerized workload might be a good example.
• Be sure to pin these environments.
• Give some advice for how to adopt this safely at scale: get something working end to end, then fan out. (This needs to be more fleshed out.)