The current output for `--help` is quite messy and hard to
navigate.
I added some indentation and spacing to make the document
easier to read. For example,
File and expression options:
-e <exprs>, --eval <exprs>
Evaluate <exprs>, print results
-f <file>, --load <file>
Like -e '(load "<file>")' without printing
The new layout is longer, but at least it is readable. It
might be better if we could move all the options to a man
page and only select a few common ones to put in `--help`.
