improve parsing inline markdown
add find_first
use find_first in inline parsing
doc love
userguide display improvements
move cache and formatting utils to userguide.util
handle language names, improve credits page
about dlg: get credits info from userguide
move external changes to new userguide
edit in place userguide
remove old help pages
remove the old help system
link musicxml import in user guide
Merge pull request #291 from mamoch/master

midiinput: pitch language and chord mode
add some info to engrave custom help page
shorter titles
better align
add 404 page when a non-existing userguide page is requested
midiinput: changed classes to new-style