differ 1.2.0 stable

The biggest change for sure, renamed hxcollision to differ
Now that the library is getting more use its better to have a consistent name
and to have a more explicit path. Think of "differ" as a diff tool for shapes/rays,
it tells you how shapes differ (i.e the separation).

Change notes, thanks to @PDeveloper for work on the the rays and @ubald for fixes and testing.

• Added ray collision information, rather than just true/false
• Added ray vs ray intersection with info on overlap
• Added more granular tests, that will expand further
  • New test case uses luxe http://luxeengine.com/
  • hxcollision/differ was born for luxe.collision, separate for any framework
• Refactor continued separating code for future 3D vs 2D
  • moved all internal 2D code into differ.sat.SAT2D
  • moved all internal common code into differ.sat.Common
• Renamed Collision.test to Collision.shapeWithShape
• Renamed Collision.testShapes to Collision.shapeWithShapes
• Renamed Collision.rayShape to Collision.rayWithShape
• Renamed Collision.rayShapes to Collision.rayWithShapes
• Renamed Collision.rayRay to Collision.rayWithRay
• Renamed Collision.rayRays to Collision.rayWithRays
• Renamed Collision.rayRays to Collision.rayWithRays
• Renamed data.CollisionData to data.ShapeCollision
• Renamed data.RayCollisionData to data.RayCollision
• Renamed data.RayIntersectionData to data.RayIntersection
• Removed OpenFLDrawer, will replace with gist or test later