Possibility to delete some old versions

When we create some modifications on a page, of course, there is a new version... and this is great. However, It will be very interesting to purge some versions to keep a clean database. We can imagine, that we can't purge the first version, but we can have:

First step:

Version 1
Version 2
Version 3
Version 4
Version 5 (current)

I decide to purge the two older versions, it remains

Second step:

Version 1
Version 4
Version 5 (current)