getConvexHull returns upper and lower part of the c-hull seperately
Declutter getConvexHull code.
New clip convex-hull routine
New CurveCurveINtersections code; doing the fatline clip inplace.
Modify old clipFatline code to a much cleaner version
Fatline clipping: Iterate to find intersections
Fatline clipping: new #CurveIntersections method
Fatline clipping: remove old fatline code. This is handled by the CurveIntersections method now
Fatline clipping: clipConvexHull method handles only the clipping part
Remove debug helpers
Fatline clipping: remove old #curveIntersection method
Fatline clipping: fix issue where one of the curves has been converged completely and other hasn't.
Fatline clipping: fix convergence check to be more strict
Remove enpoint fix from curve-line intersections, since it's already handled
Merge branch 'master' into fatline

* master: (71 commits)
  Define the default value for Color#alpha.
  Some minor changes in Satie example.
  Include point property in stroke hit-results.
  Clean up code and comments in various places.
  Use Point.read() for center parameter in Item#rotate
  Make hit-tests work again with projects that don't have a view.
  Write documentation for Item#anchor.
  Keep support for Item#registration for now as well, since there are some scripts on the mailing list that use it.
  Rename Item#registration to Item#anchor
  No need to run Radial Rainbows in HiDPI mode.
  Include Satie Sound Analysis Example.
  Only start dragging if none of the mosedown events have stopped propagation.
  Fix item-level mousedrag events again.
  Allow layers to select children again, since it breaks examples otherwise.
  Fix documentation issues in TextItem.
  Make hit-test tolerance dependent of view#matrix
  Implement options.selected for hit-testing segments and handles.
  Fix typo in new segment / handle hit-testing code.
  Use same stroke tolerance approach for hit-testing joins and caps as well.
  Do not factor in view matrix into Item#globalMatrix.
  ...
Fatline clipping: fix c-hull corner case.
Clean up coding style a bit.
Use correct value for tolerance in non-fatline code again.
Further simplify code a bit.
Some more variable renaming.