KM 2.2.0 - rationalizing behavior on errors

[Pete]

I've just uploaded KM 2.2.0. This rationalizes the parameters
controlling KM's behavior on error into a single variable, as
described below from the RELEASE-NOTES.txt:

2.2.0 - **NOTE**
The parameters controlling behavior on errors have been
rationalized
to a single parameter. *abort-on-error-report*, *error-report-
silent*,
and *silently-abort-on-error-report* NO LONGER DO ANYTHING.

Instead use the NEW variable *on-error* to define behavior on
errors,
with the following allowed values:
VALUE KM'S BEHAVIOR ON ERRORS
===== =======================
abort Report error and do not continue, instead
immediately return NIL.
abort-silently Don't report error and do not continue, instead
immediately return NIL.
debug Report error and turn on debugger [DEFAULT]
continue Report error and continue.
ignore Don't report error and do continue.

e.g., (setq *on-error* 'continue)

NOTE that with continuation (*on-error* = continue or ignore),
KM will
(as before when *error-report-silent* was t) assume a value of NIL
for the computation where the error occurred. Again as before, this
may cascade to cause other errors and may make the results of
computation invalid, so use these two values with care.