[xacml] [CR] Make "gregorian" functions non-mandatory

Text Changes:

  Section 11.1.4(?) [Conformance] Functions

  Remove "M" from left column of urn:oasis:names:tc:xacml:1.0:function:gregorian-equal

Rationale:

  We already support xs:date, so support for Gregorian is icing
  on the cake.  Also, I haven't found a standard for "gregorian",
  so it is hard to develop tests for it.

Anne
-- 
Anne H. Anderson             Email: 
Sun Microsystems Laboratories
1 Network Drive,UBUR02-311     Tel: 781/442-0928
Burlington, MA 01803-0902 USA  Fax: 781/442-1692