Spacing: line spacing and Y stems

[clairelindsey]

:: Font feature/linespace control spacing lines at % of y-stem

@dberlow could you tell us a little more about how you'd like this example to function? Thanks :)

[dberlow]

Please see PDF enclosed and use better looking styles than I selected. Linespacing example1.pdf

[ghost]

@dberlow I know you're off today, but teeing these up for later.

Do you want this to be merged into the #37 vertical paragraph spacing, or is this a separate spacing demo?