Code review comment for lp:~niedbalski/charms/trusty/percona-cluster/fix-1425528

After further discussion, the innodb-buffer-pool-size seems to have the same definition as the datasest-size. The innodb-buffer-pool-size config-option is being provided as a means of being explicit in what option within percona this value is setting. The dataset-size option was previously used to configure this however it didn't appear to be working due to the preferred engine not being set.

I think with the log entry indicating that the dataset-size option has been deprecated we should also make an announcement in the overall config.yaml file telling the user that this has been deprecated.