LDEV-3115: Fix rubbish bin functionality when canvas gets scrollable. Add properties dialog contents for Tool and Grouping activities. Allow choosing Grouping for a Tool activity. Redraw activity when its properties changed.
LDEV-3115: Open activity authoring on double click. Prevent double clicking from starting drag&drop action. Add partially functional Open Sequence interface.
LDEV-3115: Add gates. Fix Flow button dropdown issue. Use single properties dialog for all activities. Fix properties dialog appearing on IE and Chrome.