Revision history for Perl extension Request.

0.01  Sat Feb 24 13:12:05 1996
	- original version; created by h2xs 1.16
0.03  Renamed to DataFlow
0.04  Renamed to Data::Flow
0.05  Made new() use two arg version of bless to allow subclassing.
0.06  'process' was misdocumented.  Correct, and add 'oo_process' which
      matches the old docs for 'process'.
0.07  Add aget() and oo_output method
0.08  oo_output and SYNOPSYS example made correct. 
0.09  New inference type 'self_filter'.
      New method already_set().
      Move test to ./t.
      Undocumented method unset().
      Allow 'prerequisites' to be supplied alone if it sets the value.