History of plural 1 change

In src/cli/format.rs, lines 19–21 on b3e60590316403ebed833ca1d19262bd7df3365f20010ae74c55946210c2d63c. Every change that wrote or deleted one of these lines, or deleted a line from between them. Exact, because each line keeps its identity across edits; edits elsewhere in the file are not here. Also: oxy log -L 19,21:src/cli/format.rs.