Improve failed mysql node removal time in HA deploys.

Improve failed mysql node removal time in HA deploys.

In HA deployments, we now check mysql nodes every 1s and removed them
immediately if they are failed. Previously we would check every 2s and
allow them to fail 5 checks before being removed, producing errors from
other OpenStack services for 10s, which causes confusion and delay for
operators.
Additionally, these check options are now also a class parameter so can
be overridden by operators.

Closes-Bug: #1639189

Change-Id: I0b915f790ae5a4b018a212d3aa83cca507be05e9