iris pm2 prom and standalone library code

version 3.1 November 14, 1984 -
	introducing the "b" command.
	bugs in various drivers.
version 3.2 December 10, 1984 -
	medium-independent boot command.
	bugs fixed in various drivers.
version 3.3 January 4, 1985 -
	can handle the ip disk drive.
version 3.4 February 4, 1985 -
	move special area including stack+bss+io
	to the LAST half-meg of mem after sizing.
	fix "d" command.
version 3.5 February 6, 1985 -
	combined gl1 / gl2 proms.
	scrolling.
	eliminated "Sys3" tools.
	device drivers ignore fstype.
version 3.6 February 28, 1985 -
	boot from multibus proms.
	fix bug in bigbooting.
	fix bugs in termulating (microsw).
	March 10, 1985 -
	added msdelay() calibration
	fixed rs170 clear
	fixed autoboot md:
version 3.7 March 19, 1985 -
	improved sa lib.
	fixed <break> from program.
	improved scrolling.
	eliminated !* split screen.
	improved terminal emulation:
	added "transmit" feature - \EN
	somewhat improved nx driver
	fixed leading 0 bug where insisted on 0x, 0o, or 0t
	fixed clear bug (t - vi) disappearing cursor.
version 3.8 August 2, 1985 -
	added efs support
version 3.9 November 8, 1985 -
	added multiple indir extents (ugh)
	19200 baud termulating fix
	DTR termulating fix
version 3.9 February 19, 1986 -
	can load bootable prom image at addr >= 0x100000

10dec84 -
in order for the Makefiles to work correctly,		XXX
./Sys3lib should be moved to /Sys3lib			XXX
./Sys3bin should be moved to /Sys3bin			XXX

 3jan85 -
mon/adv*.c may be sacrificed to save space.

12feb85 -
Sys3 tools no longer needed.
BUT MUST USE ./segld which is ld hacked to take -LD

30may85 -
created "promsplit" for burning 1 at a time.

2aug85 -
added efs support

8nov85 -
19200 baud fix
DTR fix
deleted extraneous net junk

19feb86 -
fix memclr() to preserve prom image even if addr >= 0x100000
