Version 0.71.  This has all the drivers in and active for the Duet expansion
board for multi-material printing.  It should (!) also work on a standard Duet with
the only strange behaviour being that you get funny temperatures for the non-existent
heaters. Note that you now have to define and select tools:

M563 P1 D0 H1 ; Define tool 1 to use drive 0 and heater 1
G10 P1 S185 R100.0 ; Set active and standby temperatures for tool 1

T1 ; Select Tool 1
M116 ; Wait for all temperatures

Don't use M104 and M109.

The first line, and possibly the second, could go in config.g.  The third
and fourth go in your G Code program.  See: http://reprap.org/wiki/G-code