d recognizing a mediation privilege where litigants can "rely on the confidential treatment of everything that transpires during mediation . . . ." Lake Utopia Paper Ltd.l. Connelly Containers, Inc., 608 F.2d 928 (2d Cir.1979); Folb I. Motion Picture Ind. Pension & Health Plans, 16 F. Supp. 2d 1164, 1173 (C.D.Ca. 1998