fix #40846: require Ctrl+drag to create staff-only barline change
fix #31856: add option to trim whitespace from exported PNG
Merge pull request #1510 from MarcSabatella/40846-ctrl-barline

fix #40846: require Ctrl+drag to create staff-only barline change
fix mtest
Merge pull request #1514 from MarcSabatella/trim-option

fix #31856: add option to trim whitespace from exported PNG