fix bug in footnote
add prompt directive
action to show directive examples
added the aside directive
add TaggedSource
new version of markd highlights differently
rework the code directive.

can filter lines by source tags
refactor TaggedSource
TaggedSource#getOutput
fuss
add select all to tagged source
change getOutputLines to return line numbers
add github syntax coloring
add pygment npm package
add SourceFormatter
code directive uses SourceFormatter
code output html normalization
highlight source
tweak formatting behaviour
use source formatter to render md code blocks