This method does protect recipient metadata but doesn't support multicasting so
if a mail has N recipients N copies of the mail need to be sent to the group
RsGenExchange made some members protected instead of private so child classes
can use them
Create Rs{G,N}xsMailPresignedReceipt items to prepare and dispatch receipts
Move RsNxsMsg deserialization to RsNxsMsg::deserialize(...) method
Add notice about param not being checked in GxsSecurity
Use proper types for RsGenExchange::getMsg* params
Implement bitwise or and not operators for t_RsGenericIdType
GxsMail unsubscribe old unused groups
GxsMail initial work on supporting client services
Implemented p3IdService::encryptData(...) for multiple recipients