Right now, the custom actions "OnChange" function is this:
public function onChange( $member, $oldPackage )
However, there is no straightforward way to obtain the related purchase data from this.. (see topic above). It would be really great if onChange, and maybe other functions where it applies, to send the $purchase data with it (the row from nexus_purchases)
E.g.:
public function onChange( $member, $oldPackage, $purchase )
