re_intuit_start(): add more debugging output

re_intuit_start(): add more debugging output

Add some debugging output to some parts of the code without them, so it's
easier to follow progress through intuit(); also add an initial "we're in
intuit" message.

Make all the debugging output, apart from the initial and final intuit
messages, indented by 2 chars so that they are seen to be things happening
within intuit.

Dump the susbtrs data array.

Fix up a few of the existing outputs to be more informative.