[m-rev.] for review: changes to option handling

[Zoltan Somogyi]

This email has two purposes. The first is to seek a review from anyone
of the attached diff and log for a change to getopt_io.m, including
specifically about an XXX in the description of the new exported predicates.
(The diff is with -b.)

The second is to seek opinions from everyone about the proposed
next steps, one of which is also the motivation for the change to getopt_io.m.
These are described in the attached file OPTIONS.

Zoltan.
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