* remove unfinished polygon and remove selectable for shapes in polygon mode
* make group and polygon position remain inside canvas area
* click through transparent area in grouped object
* add some shortcuts for basic usages
* tools button icon in center & switch mode border
* fix load svg image
* basic rtl support, panzoom have issues in rtl mode
* better zoom option both in ltr and rtl
* handle zoom event in mask editor
* add h button to handle toggle mask
* add more mime type
* use capital M (shift+m) for toggle mask
* allow io shortcuts in mask editor only
* make other shapes also remain in canvas bound area
* better zoom implementation, zoom from center
add zoom to resize event listener
* add a border to corner to handle blend of control
* add refresh button to go to selection menu
* add tooltip to shortcuts and also add shortcut for other tools
* make opacity remain in same state when toggled on
* opacity for group/ungroup objects
* update shortcuts implementation
