Add more argument validation and tests for QuadTree()
Merge branch 'hotfix/quadtreeArgsValidation'
Fix Assertion failure with node-canvas on Node.js
disable bitmap smoothing by default

bitmap smoothing doesn't work well with the art of most 2d games.
Considered undesirable.
add bugfix for missing image data when creating from source

node-canvas does not handle default arguments correctly for
"ctx.drawImage".
Add tests for Bitmap()
remove unnecessary async callback in all tests
Merge branch 'hotfix/bitmapTests'