refactor formating to be more flexible
only change bg color for alt rows, not full format, and only set fg color if actually set in column
start adding "public" colors to rendering
actually a more generic name would be better in case theme isnt always grey
add alternating bg color for tables
oops this was not supposed to take an argument
allow configuring task lists with alternating bg
add alternating bg color
adjust alternating bg color. it is still not nearly subtle enough but it is the best i can do
draw aligned text for headers too
ensure drawing fills space both before and after text for non-standard alignments