cluster: bump nearly-expired certs

This makes clustercfg ensure certificates are valid for at least 30
days, and renew them otherwise.

We use this to bump all the certs that were about to expire in a week.
They are now valid until 2021.

There's still some certs that expire in 2020. We need to figure out a
better story for this, especially as the next expiry is 2021 - todays
prod rollout was somewhat disruptive (basically this was done by a full
cluster upgrade-like rollout flow, via clustercfg).

We also drive-by bump the number of mons in ceph-waw3 to 3, as it shouls
be (this gets rid of a nasty SPOF that would've bitten us during this
upgrade otherwise).

Change-Id: Iee050b1b9cba4222bc0f3c7bce9e4cf9b25c8bdc
20 files changed