Enhancement : Possibility to resize canvas content during resize

- new checkbox in resize panel
- content is resized using nearest neighbor
- deactivated by default

2 bug fixes :
- remove focus after closing drawer
- fire resize event after undo/redo if size changed
Fix : Fixed styling for resize content checkbox
Merge pull request #175 from juliandescottes/feature-resize-content

Enhancement : Possibility to resize canvas content during resize
Enhancement : full piskel build deployed to dest

Use grunt [default] to build the application.
Target dest with a webserver to launch the application.
Added grunt server task to run server+watch
Merge pull request #177 from juliandescottes/enhance-build

Enhance build
Build : Added grunt server:debug target
Added grunt server and server:watch tasks
Merge remote-tracking branch 'upstream/master'

Conflicts:
	Gruntfile.js
Setup nw releases destinations to build folder.