trivially correct a spelling mistake in CenterPertubVisibleSupportDomainSearcher
make RawSupportDomainSearcher accommodate null segment searcher
Move Miscellaneous.tidy() to UIUtils, and replace UIUtils.tidyRectangle2D()

  - modify TriangleAdaptiveCellFactory accordingly
Make Segment2D implements UnivarArrayFunction
Make Segment2DQuadrature depend on Segment2D's UnivarArrayFunction implementation
Enlarge ScaleIndicator font and change the default color to green
make BasicModelPanel opaque and white
change the default filling color of SingleModelShapeDrawer and also let the alpha filling parameter work
Trivially tidy TriangleContourBuilder code and make the TriangleContourBuilderDemo more customizable.
in Polygon2D add a constructor without arguments
add UIUtils.pathIteratorToSegment2DChains()
add Circle
add RectangleWithHoles and its demo