First working port of builder.js, WIP.
Checkpoint 2.
Checkpoint 3
Stop drawing strokes when lineStyle width is set to NaN
Merge branch 'nat' of https://github.com/mozilla/shumway into nat
Round Graphics lineStyle to pixel values
Remember drawing cursor position over Graphics drawing style changes
Stricter types, extracted block builder state into a new class.
Separate fill from stroke geometry in Graphics drawing

This is a prerequisite for two things:
- Implementation of separate switching of fill and line styles while drawing a single shape
- "Fixing" the position of thin lines to always align on pixel boundaries, even if they should be 0.5px off
Merge pull request #1324 from tschneidereit/gts

Graphics drawing progress
fixes some minor mouse cursor issues

cursor was reset when pointer leaves owning element