To-do list


Change storage to allow matrices of things to be displayed, all
using the same conventions:  main table in the middle, row and column labels to the left and top respectively, plus new matrix in 
top left --- or even larger matrices to allow labels on all sides.

Add conversion of result to kable() format, so kableExtra()
formatting tweaks can be applied.  DONE

Fix placement of Hline label. DONE

Add character.only to Heading().  DONE.

Add support for nice formatting of tables of raw data. DONE

Check that arguments of Pseudo-functions use match.call. DONE

Add support for editing the labels on a table. DONE
