Add +scl and +sub support

Partially addresses #108.  Both flags (but especially "+scl false") is
necessary (in part) for avoiding scheduler collapse, even with R16
(sadpanda).

See also: PR #162

Why are words hyphenated at the ends of lines? Also, the spacing is inconsistent as if it were trying to justify the right column. This may be find for the editor, but will not look good on the console for the `describe` command.