Enhancement: Truncate by date instead of count

[davejtoews]

In some cases total count of Versions is not the ideal metric. I have records for which I may wish to retain version history for a set number of months. The ability to run a task which deletes all non-live versions from before X date, or from X number of days prior to the current date would be a handy feature.

[michalkleiner]

That's not a bad idea @davejtoews, would you want to have a go at adding that config option and opening a PR?

[axllent]

I'm not quite sure how you would handle all the potential various requirements for something like this, but as @michalkleiner said, I'd be open to a Pull Request which allows the flexibility if there is a way to do it.