Update polygon.class.js

Now polygon Top and Left can be setted in the contructor call or calculated by the points.
Update polyline.class.js

Mirror polygon changes
Update polygon.class.js

!options..left would fail in case of left = 0.
Update arc.js

Fix useless optimization of code that was rendering arcs not correctly
Merge pull request #1646 from asturur/Fix-bad-optimization-in-arc.js

Update arc.js
bugfix: add toObject so Blend can be serialized
bugfix: add toObject so Blend can be serialized (extend not needed)
Merge pull request #1639 from asturur/Polygons-and-Polylines-top-and-left-property-precendece

Polygons and polylines top and left property precedence
bugfix: add toObject so Blend can be serialized (added missing ;)
Merge pull request #1654 from zigotica/patch-1

bugfix: add toObject so Blend can be serialized
Update path.class.js

Like any other shape in fabric, when exported to svg, the shape has to be translated around origin.
This additional translation brings it there.

Fixes svg export of paths OUTSIDE of path-gropus. Inside was already ok.
Update path.class.js

Fixes == with ===
Update polygon.class.js
Update polyline.class.js
Update polyline.class.js
Update gradient.class.js
Update object.class.js
Update object.class.js

Fix code style error.
Merge pull request #1665 from asturur/Fix-Gradient-part-3

Fix gradient part 3
Merge pull request #1664 from asturur/Polygon-and-Polylines-code-reduction

Polygon and polylines code reduction