loadbalancer: fix MySQL timeout HAproxy config

loadbalancer: fix MySQL timeout HAproxy config

Current HAproxy config is broken for MySQL timeout parameters.
This is what we have today by default in HAproxy logs:
--------------
[WARNING] 238/115010 (13878) : config : missing timeouts for proxy
'mysql'.
| While not properly invalid, you will certainly encounter various
problems
| with such a configuration. To fix this, please ensure that all
following
| timeouts are set to a non-zero value: 'client', 'connect', 'server'.
--------------

This patch aims to:
* Use the correct parameters to configure puppetlabs-haproxy
* Update the database timeouts to higher values to prevent the
services from disconnecting too frequently by setting the Galera HAProxy
timeout to 90 minutes.

Change-Id: I06dd4bf81d4f4fd3c01bb681f6f0b3152f2b8eea