Prototyp svg output gradient/pattern
Valid svg output (http://validator.w3.org/):
- delete width/height attributes from g (http://www.w3.org/TR/SVG/struct.html#GElement) and path element (http://www.w3.org/TR/SVG/paths.html#PathElement)
- update DOCTYPE for svg version 1.1
drawCorners -> drawControls, for consistency. Remove unused hasCorners and use hasControls instead of hideCorners. Version 1.0.12
Merge pull request #437 from Kienz/svgOutputValidation

Ensure valid SVG output (http://validator.w3.org/)
Merge remote-tracking branch 'origins/master' into sketch