Use plain Unicode instead of LaTeX in rich text :table output

LaTeX formulas inside tables cause various layout issues in Jupyter
Notebook, such as long sets being wrapped even when they would fit on a
single line, table columns being wider than necessary, and LaTeX
formulas being left-aligned instead of right-aligned like normal text.
1 job for master in 2 minutes and 31 seconds (queued for 5 seconds)