In this preliminary test of a modern score, the staff lines are washed
out temporarily. This is done by making a tuned StaffContainer,
which \skips some notes without printing lines either and
creates a \new Staff then in order to create the lines again.
(Be careful if you use this; it has been done by splitting the
grouping Axis_group_engraver and creating functionality into
separate contexts, but the clefs and time signatures may not do
what you would expect.)