Introduce a new function called is_ip_addresses which will verify
if a string or an array of strings are composed of correct ip addresses.
We do this in order to fail a bit more clearly if we are passed an empty
or broken ip address. Without this the failure will be in pacemaker
failing to start a VIP called 'ip-'.
Also convert the only use of legacy is_ip_address stdlib function in
mysql::client to this new function (for consistency reasons).
Suggested-by: Rhys Oxenham <roxenham@redhat.com>
Change-Id: Ie15c585a9a902b577f35a75de191bfa91c132668