For discussion: Add page about our commitments

1. I wasn't sure what to call it. "Our commitments"? Or is it fine as is?
2. I think it's fair to say we'll respond to email as soon as we can during working hours? (Just to stress here, I really want us to make sure we do not respond out of working hours as I don't want that to become an expectation).
3. Any other thoughts?
Rephrased to leave out the security issues. I've only said 'it may take a while'. If it's a security issue it won't take a while. If we have more information about a process for security issues, we can add that later. (We have a story for that in the backlog).