Migration numbers need to be consistent between version upgrades.
The migrations for the key lifecycle management were merged
into v0.11.1 as number 56, but are currently 58 in main.
This reorders them down to 56, fixing an issue when
migrating from 0.11.1 to main.
Fixes the comments on functions wt_add_seconds, wt_add_seconds_to_now,
wt_sub_seconds, and wt_sub_seconds_from_now which were the tragic
victims of a copypasta error.