basic fix for drag select and zooming for touchscreen
Improve event propagation
Improve drag for touchscreen
Bug fixed for menu interaction
Improve transition for new added node in tree layout
Improve menu touch interaction
Improve brush and zoom behavoir for touch screen
Refind code indentation
Bug fixed for lifting one finger during zooming
Support create link on touch screen
Add prompt message for operations without feedback.
Bug fixed for Safari which doesn't have TouchEvent Class
Improve mode update mechanism. Add mode toggle button. Bug fix for add node with click
Prevent zoom on iPad. Add comments and reorganize code.
Adjust mode button size
Add rotation function by 90 deg with transition