- Updated Grid and added CommunicatePersonIdField so that Grids that have IsPersonList enabled can figure out which field of the dataset the personId is (it defaults to [Id])
- Update GroupMemberList block to set Grid's CommunicatePersonIdField to PersonId since the Id of the dataset is just the GroupMember.Id, and the Communication needs to know that the PersonId field is PersonId in this case.  This fixes a bug where clicking Communicate on the GroupMemberGrid would not populate the list of recipients correctly.