ascii: Don't print command names in output.

This seems to be closer to what users expect.

I think that having the command names in output was being confused
by users with SET PRINTBACK=ON (see e.g. bug #31561) even though I
really just added that so that there are clear titles for the output
that goes with each procedure.  This change should help, I think.

It might make sense to make drivers only print the titles of
procedures that have other output, but this commit doesn't do that.