This is based on a disassembly of the binary AI:SYS1;TS FACTOR; the
binary and its help file .INFO.;FACTOR ORDER are both dated 1977-09-27.
MC had an identical copy with a later date.
This assembles into a binary that's identical to the original, except
that the original version has all its symbols marked as global, and no
assembly info.
Fixes#96.
