* 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
* Add text tool to IO
* Remove unnecessary parentheses
* Fix text objects always grouped
* Remove log
* Fix text objects hidden on back side
* Implement text scaling
* Add inverse text outline
* Warn about IO notes with only text objects
This will result in a different error message than the case where no
objects are added at all though, and the user can bypass the warning.
Maybe this is better to avoid discarding the user's work if they have
spent some time adding text.
* Add isValidType
* Use matches!
* Lock aspect ratio of text objects
* Reword misleading comment
The confusion probably comes from the Fabric docs, which apparently need updating: http://fabricjs.com/docs/fabric.Canvas.html#uniformScaling
* Do not count text objects when calculating current index
* Make text objects respond to size changes
* Fix uniform scaling not working when editing
* Use Arial font
* Escape colons and unify parsing
* Handle scale factor when restricting shape to view
* Use 'cloned'
* Add text background
* Tweak drawShape's params
