Notification in Confluence UI if database is using an unsupported character set or collation

Adding a warning into the install process that will alert installers that their database is using incorrect (and often default) settings. For instance, MySQL will default the character set to latin1 instead of utf8. The error could be similar to the notification that REPEATABLE-READ is no longer supported and the database must be configured to use READ-COMMITTED. This would help prevent a number of issues related to misconfigured database schemas.