[REQ] Improve CLI output for prune command when using retention policies

Minor addition to text that’s output when doing CLI prune command using retention policy (i.e.

duplicacy prune -keep <n:m>

At the moment, the command:

duplicacy prune -keep 360:1800 -keep 90:360 -keep 30:180 -keep 7:90 -keep 1:30

will show this info. on what snapshot’s will be kept:

Storage set to <Storage_URL>
Keep 1 snapshot every 360 day(s) if older than 1800 day(s)
Keep 1 snapshot every 90 day(s) if older than 360 day(s)
Keep 1 snapshot every 30 day(s) if older than 180 day(s)
Keep 1 snapshot every 7 day(s) if older than 90 day(s)
Keep 1 snapshot every 1 day(s) if older than 30 day(s)
No snapshot to delete

I know it’s already implied, but can you add an extra line, to make it explicit that all snapshot’s will be kept for 30 day’s: e.g.

Keep all snapshot's for 30 days

so, using command above, it would output the following instead:

Storage set to <Storage_URL>
Keep 1 snapshot every 360 day(s) if older than 1800 day(s)
Keep 1 snapshot every 90 day(s) if older than 360 day(s)
Keep 1 snapshot every 30 day(s) if older than 180 day(s)
Keep 1 snapshot every 7 day(s) if older than 90 day(s)
Keep 1 snapshot every 1 day(s) if older than 30 day(s)
Keep all snapshot's for 30 days
No snapshot to delete