Remove support for 'userlocks'?

According to our documentation, 'userlocks' were removed in PG 8.2:

	http://developer.postgresql.org/pgdocs/postgres/runtime-config-developer.html

	trace_userlocks (boolean)
	
	If on, emit information about user lock usage. Output is the same as
	for trace_locks, only for user locks.
	
	User locks were removed as of PostgreSQL version 8.2. This option
	currently has no effect.
	
	This parameter is only available if the LOCK_DEBUG macro was defined
	when PostgreSQL was compiled.

Should we remove this parameter and the supporting code since pre-8.2 is
now end-of-life?

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +