Deployment strategies

[giacmir]

Hello,
I wanted to ask your thought about automated deployments. As an agency with a high automated development process we are struggling with some issues:

1. plugin status is saved into the database and can't be source-controlled, how to handle this during automated tests and deployments?
2. what is exactly the role of psh.phar? is meant as a development tool or it is somewhat required in production too to perform specific actions during deployment?
3. How to deploy shopware on a multi-server architecture. Is there redis support for sessions and cache?
4. Do you plan to support full page caching engines such as Varnish?

Thank you.