fix menu roles in global menu
Merge pull request #360 from dliessi/globalmenu-roles

fix menu roles in global menu
generalize menu roles determination
make prefs running correctly from global menu

TODO: make it possible to run Preferences without a Main Window
add recent files to mac global menu
show an empty document when the window is generated
add score wizard to global menu
create a mainwindow if there is none, when called remotely to e.g. open a file
upd chlog
add file→new from template to global menu
add file import musicxml to globalmenu
deleteLater does the trick
add Window→New to global menu
add sessions menu to global menu
support standalone durations in music
save session on window close, not app quit

otherwise we would overwrite a session as soon as a new window pops up
So the global menubar mode is sessions-less.
new feature: wrap long lines, fixes #45.

this is only a visual worp wrap, it avoids the horizontal scrollbar.
later we can add formatting commands that wrap long lines, put a measure or long commands on a single line etc
new option to set the anti-alias-factor in the custom engrave GUI.

fix #361