README updates needed

[eefahy]

• [x] If the stack needs to be created outside of us-east-1 the stack will need to access deployment artifacts in the desired zone
• [x] there's some manual https stuff needed
• [ ] Turn on versioning for S3 bucket used for artifacts
• [ ] Initial account creation parameters that need to be set (rails secret hash, database password, honeybadger key, etc)