Adding notes deletes contents of unrelated staff if linked staves present
Ubuntu 14.04, GIT commit: f953fe7
1) new score, flute + guitar, add linked staff to guitar staff
2) add note to flute staff
Result: the measure rest is deleted from the top guitar staff
Similarly, adding note to top guitar staff removes the measure rest from the flute staff
Somewhere we must be off by one with a staff index?