Updates, tweaks, additions.

Some updates, proposed additions/changes.
- Update Readme.md to reflect change in upstream repo location.
- Merge some updated syntaxes from upstream.
- Propose adding a few syntaxes not presently included (useful to me... maybe others?)

See commit log for details.  

I realize this is not exactly a small pull request, so I haven't squashed the commits
(in case you want to cherry-pick some, and/or go a different direction on others).

Thanks for all your work, Professor M! :school:
  
:wink: