* Fix tty_ify bugs and refactor
* Move tty_ify() and supporting attributes to the DocCLI class as that's
the only thing using it.
* Add unittest for the code.
* Fix a bug where the substitution macros can be detected when they are
a part of another word.
* Add support for L(), R(), and HORIZONTALLINE which were added to the
website docs many years ago.
* Update test/units/cli/test_doc.py
Co-authored-by: Matt Clay <matt@mystile.com>
Co-authored-by: Matt Clay <matt@mystile.com>
