Hi,
our development lifecycle includes the following steps:
1. create a clean DB
2. copy the schema + subset of data from prod
3. run liquibase update
Step 2 takes something like 2 hours, and the easiest would be to be
able to do something like `liquibase lock "DB is being copied
from prod"` before it, and `liquibase releaseLocks` after it, so
that noone could accidentally start step 3 too early.