Domible

- added <hr> (HorizontalRule) element to sectioning
- added ability to save html doc to a file in open_html_in_browser
- and now setting encoding correctly to utf-8 when writing to file (saved or temporary)

- more tweaks to tools and updating other areas to use tools
- updated some dependencies
- been focused on work and some volunteering stuff, hope to get back to this soon...

- more tweaks to element_from_object
- added open_object_in_browser to tools.
now, in the REPL, I don't have to call element_from_object then open_in_browser.

- tweaks to element_from_object.
I didn't like the way headings read out within list items.
Also, treat empty objects like terminals, simple print statement.
I think it's a bit cleaner this way.

- WARNING - Breaking backward compatibility with this release
- changed several methods and variable names to snake case (Hey, kool aid!!)
- added element_from_object to domible.builders, including simple test script (efo.py) in tests directory
(not tied in to pytest though)
- added add_sublist to ListBuilder to address HTML/CSS issue with extra "bullet point."
(see comments in ListBuilder.py for more details)
- ran "poetry up" to update all version constraints in pyproject.toml
- updates to docs available at [github pages for the domible repo](https://joeldodson.github.io/domible/).

- kind of getting back to domible
- to use with another project, added a 'tools' module under domible
- added open_in_browser and save_to_file in tools