RapidComposer updated to v3.66

[msmcleod]

March 21, 2019: v3.66

• A crashing bug fixed when right clicking on the structure bar
• [macOS VST] 'Bring RapidComposer To Top' button works well, UI fixes
• Fixed: displaying lines/parts with various signatures was incorrect
• Improved handling of zero-length notes during MIDI drag and drop

To upgrade, hit the "Check for Updates" button on the Support menu.