fixes https://github.com/TryGhost/Team/issues/2461
- Ignores 'edited' links when there is only one second differences.
- Make sure we don't set updatedAt when linking a post to a redirect
refs https://github.com/TryGhost/Team/issues/2400
- we've deemed it useful to start to return `Content-Version` for all
API requests, because it becomes useful to know which version of Ghost
a response has come from in logs
- this should also help us detect Admin<->Ghost API mismatches, which
was the cause of a bug recently (ref'd issue)
no issue
- The sleep method has been used in 8 modules reimplementing the same thing over and over again. It's usually a sign of async event processing outside of the request/response loop. It's good to have a single point of implementation for a "hack" like this, so we could track it easier and address the even processing delay in a more optimal way centrally if it ever becomes a bottleneck
