fix #3510 and better handling of timesigs when deleting measures
Fix #20096: Chord name navigation

Provides the following navigation in edit mode for Chord Names:
Tab/Shift-Tab - start of next/previous measure.
Space/Shift-Space - next/previous note, rest or chordname.
;/: - next/previous beat, according to time signature.
Ctrl-1..Ctrl-9 - move forward by specified duration (like f.b.).

There are still issues of layout and display to address, but they
will be approached separately.
Add missing changeState() to lyricsUpDown()
Remove unnecessary parent checks harmonyEndEdit()
Correctly read hexadecimal codepoints.
Correct error in last commit.
Update font name and Unicode code points for 2.0
Note::updateAccidental() no longer removes ACC_USER accidentals
Score::upDown() removes all accidentals when changing pitch or tpc of a note
Note::updateAccidental() uses clone() to preserve accidental properties
loose CMake minimum version requirement
clean Makefile.mingw a bit
travis-ci: install cmake from ubuntu repository
travis-ci: install and use gcc 4.7
travis-ci: install g++4.7 non interactively...
travis-ci: limit number of CPUs used during compilation
TAB: make "Stem through staves" option more similar to regular pitch layout.
Merge pull request #245 from mgavioli/TAB_stems_through_staves

TAB: Stems through staves option
travis-ci: fix multi cpus build
TAB: do not draw stem portions between notes.

Also stop the stem a little before reaching the first note.