- Staff props dlg: added type props common to all types (num. of lines, line dist., etc.).
- Changing some type props but canceling the main dlg no longer changes the staff type.
- Fixed equality checks in EditStaff::apply().
- Both dlgs: set all buddies and proper tab order.
Also:
- Staff group names ("Standard", "Percussion", "Tablature") made uniform in spelling and translatable.
- Fixed Instrument::operator==().
Changed to a default empty string set.
This also allows to filter out TAB staff types in staff props dlg box for an instrument without strings defined.
