Option to set maximum backoff time

[FlixCoder]

Hi!

It would be great to have an option to set a maximum time for exponential backoff. So after the exponential backoff would exceed the maximum time, the maximum waiting time is used at every following retry instead. In other words, truncated exponential backoff would be nice.

This allows to retry on an e.g. daily basis when something severe happened and prevents dead job-entries that reside there for years without action. Without truncation it can happen easily that the job waits for far longer than desired (like in the scale of weeks).

Thank you

[Diggsey]

Sounds reasonable - I'd accept a PR for this.

[FlixCoder]

I currently don't have time for it, maybe at some point later :)