support check for toDataURL with quality parameter
Merge pull request #273 from Kienz/toDataURLQuality

Support check for toDataURL with quality parameter.
Add support for animating multiple properties.
Fix corner detection. Thanks Josh Pearce. Fix #275. Fix #269.
Show rotating point handle only if `hasControls=true`. Remove "hideCorners" since there's already "hasControls" property (consistent with "hasBorders" one). Version 0.9.11.
Account for bounding box in scaleToWidth/scaleToHeight. Fix #271. Version 0.9.12.
Fix `fabric.Group#toObject` not serializing children image objects. Fix #260.
Add support for switching between filled and stroked corners.
Add support for finding target per-pixel (ignoring transparent ones). This allows to drag shapes by non-transparent pixels only. Thanks Steve Pemberton for initial work. Version 0.9.13.
Fix gradient setting in loadFromJSON. Fix #246 again.
Lint everything with JSHint. Version 0.9.14.
Fix unit tests.
Fix for negative width on objects preventing selection
Remove __fontDefinitions from global props in .jshintrc.
Revert "Fix for negative width on objects preventing selection"

This reverts commit 55853039cdea47c4c26548258df0bd724b4caecf.
Fix for negative width on objects
Merge pull request #284 from sjpemberton09/Experiment

Fix for negative width on objects preventing selection.
Normalize option setting in all classes. Fix #287.
Fix comment. Fix #286.
Remove redundant bordervisibility/cornervisibility properties from image objects. Version 0.9.15.