Unixify files in POHL0000, DAIM0000, HALL0000; add a Makefile for HALL0000.

Lowercase *.c and *.h in POHL0000 and DAIM0000.
Also replace DOS line endings (CR/LF) with normal line endings (LF only)
and remove the generated file "POHL0000/ADVTEXT.H".

The original versions of these files are available in the commit
immediately preceding this one. This change makes it easier to "diff"
the three versions against one another and see what Daimler added to
Pohl's version versus what Hall added.

Source information is now available in {POHL,DAIM,HALL}0000/README.
Update the MCDO0551 READMEs.

Personal communication from Doug McDonald, 2014-03-04.
A lot of this is still fuzzy, but at least I believe this
version of events to be a lot closer to the truth than
what I'd had in the README before this change.

Mention Robert Hall's Minix port; give more information
about McDonald's and Picton's versions as far as I'm aware.

The significance of the combination to Long's safe (7-22-34)
is that it's the date of John Dillinger's death. Picton
changes it to be different in every game, and also changes
some magic words (such as PHUCE) so that they won't work
until you've "properly" discovered them.
Start work on Luckett & Pike's ADV440.
ADV440: FLY, RIDE, and SCORE.
ADV440: implement DROP and READ.
working on adv440
Adv440: dwarf toting, tides.
Implement death by thirst.
Implement owl movement and hooting.
Implement the tusk passage, and death by rats.