reorganizing and modifying examples.

cp-demo/BuildingListConstraints.scala

cp-demo/FirstClassConstraints.scala

cp-demo/enumerating/RedBlackTree.scala

cp-demo/enumerating/SortedList.scala

cp-demo/executing-specs/Calendar.scala

cp-demo/executing-specs/ListMethods.scala

cp-demo/executing-specs/RedBlackTreeMethods.scala

cp-demo/parsing/ArithmeticExpressionParser.scala

cp-demo/parsing/ParserWithNat.scala

cp-demo/parsing/PropositionalLogicParser.scala

cp-demo/stubs/NQueens.scala

cp-demo/stubs/Scheduling.scala

cp-demo/stubs/UI.scala

testcases/Test.scala