BUGFIX: set the receivers to the notifying email "To" list, rather than "Bcc" field, populate "Cc" field with current Member's email, leave "Bcc" not used for now.
BUGIX: given DataObjects' $summery_fields are so varied, and end-user of the module are likely know nothing about what is in $summery_fields, make all viewable fields to be available to notifying email template.
Temporary workaround due to ManyManyList bug in its removeAll() function.
http://open.silverstripe.org/ticket/8258