Replace TeX escape sequences with unicode counterparts

[abhro]

The default KaTeX renderer supports it, and it also clears up the docstrings when viewing in the REPL

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.11%. Comparing base (f8fd782) to head (1db90d6).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #487   +/-   ##
=======================================
  Coverage   94.11%   94.11%           
=======================================
  Files          14       14           
  Lines        2905     2905           
=======================================
  Hits         2734     2734           
  Misses        171      171           

Flag	Coverage Δ
unittests	94.11% <ø> (ø)

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[stevengj]

Do MathJaX and other renderers also support it? We also want it to work in things like Jupyter notebooks, vsCode, etcetera.

Looks like it works in Jupyter and vsCode, at least.

[abhro]

Do MathJaX and other renderers also support it? We also want it to work in things like Jupyter notebooks, vsCode, etcetera.

I don't think MathJaX supports it out of the box, in my experience, but you can use macros with Documenter to define them.

Correction: I just tested this on Pluto, and it uses MathJaX and works fine. I think that's the benefit coming from Julia's Markdown.jl parser? Either way, I think it works on all platforms we've checked, but I'd be happy to test this on other platforms as needed!