For review: Content-Base (update for mime)

PERMANENT MESSAGE HEADER FIELD REGISTRATION TEMPLATE:

Header field name:
   Content-Base

Applicable protocol:
   mime

Status:
   obsoleted

Author/Change controller:
   IETF

Specification document(s):
   RFC 2557 section 12,
   <URL:http://tools.ietf.org/html/rfc2557#section-12>
   RFC 2110 section 4.2,
   <URL:http://tools.ietf.org/html/rfc2110#section-4.2>

Related information:
   Content-Base was originally specified in RFC 2110 and
   later obsoleted in RFC 2557.  Content-Base replaced an
   older Base header field in RFC 1808, using the common
   Content-* style for MIME header field names.