Wrong spelling of pitches on MIDI import for keys other than C

Ubuntu 14.04, GIT commit: 7c37c6b

1) import attached file

Result: even though key of Db, notes are given as C#

Setting tpc's is tricky. It looks like MIDi import - and actually, several others forms of import - relies on Note::setTpcFromPitch() to do the job. However, that function does not work for notes just being added to the score for the same reason that Note::setNval() was not working a while back - the note has no parent chord yet, so the attempt to find the current key fails.

I suppose we should add a tick parameter as I did with setNval(), and update all the calls. Or maybe combine these two functions.