doc: lei q: split =item aliases onto separate lines
It makes L</--augment> look nicer without resorting to
L<--augment|/-a, --augment> and similarly verbose nastiness.
Having each option as a separate =item (with a blank line in
between each =item) seems to be the preferred style used within
Perl core documentation (I used perlrun.pod as an example),
so we'll follow Perl core style, here.
This needs to be done for other manpages, at some point...