imply expression_chart -> multiple_expressions

BUR #36353 is pending approval.

create implication expression_chart -> multiple_expressions

"A grid-like chart of multiple expressions."

I downvoted this because the expression chart format is sometimes used without multiple_expressions actually being present. Examples include post #8387397, post #3980478, post #7143582, post #1700720, post #1874588 and post #524834. The expression_chart wiki should perhaps be updated to point out exceptions like these. They are not very common, but IMO significant.