Handle intersection special case, when two curves' start and end points overlap
Add special case to examples.
Sort sub-paths before 'reorienting' during boolean calculations
Optimize Base#merge() to not use Base#each()
Various clean-ups regarding the handling of activeLayer, JSON deserialization, DOM insertion and and layer reusing.

JSON deserialization does no longer insert items into DOM twice now, and should therefore be faster.
Handle _dontFire for all component types.
Correct tolrance check (±EPSILON) in numerical solving methods.
Define Project#isEmpty()
Prevent issues with repeated PaperScript execution on same canvas and HiDPI related scaling.
Fix Path#arcBy(to, boolean)
Rename Ast -> AST
Fix typo.
Fix recently introduced issue with Node.js
Clean up smooth() code.
Simplify SVG node example.
Bump version to v0.9.13
Implement change propagation in matrices.
Rearrange method sequence in Item.
Implement setters for Matrix#translation, #rotation and #scaling.

Propagating the changes down to the owning Item too.
Allow Path#transformContent to be set to false too.