[PWG5100.19] Issue #133: Print by Reference is deprecated to remove section 4.6.2

[Issue Unconfirmed]

Since the PWG has deprecated "Print by Reference" (Print-URI, Send-URI),
section 4.6.2 should possibly be removed. Not sure if we want to wait until
those operations are obsoleted, but that might be an option as well.

Link: http://www.pwg.org/issues/133