SutherlandHodgemanClipper completed and tested. New methods for Polygon2D post 0020 release and minor bugfixes

- SutherlandHodgemanClipper completed and tested
- Circle.newBoundingCircle
- Polygon2D
  - #center()
  - renamed #containsPoly() to #containsPolygon()
  - #get()
  - #getBoundingCircle()
  - #getClosestPointTo()
  - #getClosestVertexTo()
  - #getNumVertices (deprecated #getNumPoints() )
  - #getRandomPoint()
  - #increaseVertexCount()
  - #intersectsPolygon()
  - #removeDuplicates()
  - bugfix #translate
- Polygon2D.fromBaseEdge()
- Polygon2D.fromEdgeLength()
- Polygon2D.getRadiusForEdgeLength()
- bugfix Vec2D#equalsWithTolerance() if vector is null should return false
- bugfix MathUtils#random if one parameter is passed and its an integer, return an integer