Bug: After deployment of linux formulas and salt states
/etc/security/limits.conf are not applying, as result connections
to mysql failed with error (pymysql.err.OperationalError)
(1040, u'Too many connections')

Solution: create mysql.overide, where ulimit is set to 102400

Closed-bug: PROD-8427

Because the cluster isn't managed by Pacemaker, using
majority_of_members is misleading.

This patch enables support for Grafana and provides a new dashboard.

This also installs 2 additional packages (libdbd-mysql and
python-pymysql) that are required for running the collectd plugins.

Conflicts:
	galera/master.sls
	galera/slave.sls

Conflicts:
	galera/master.sls
	galera/slave.sls