Client Statistics; new Permission Key to stop defaulting new set from most recent approved set

When adding a new Client Statistic Set, if there is an existing approved set the User is prompted "Do you want to default this Statistics Set from the most recent 'Approved' set?". This allows the User to start from the latest approved set of Statistics.

However, if this is not desirable, there is now a new Permission Key "Client.StatisticsSets.DefaultExisting" that can be denied for the User.

Note, the new Permission Key is allowed by default to maintain backwards compatibility.