fixing types for RBTree and removing .class files

.gitignore

bin/HelloWorld.class

bin/sandbox/BinaryIntExpression.class

bin/sandbox/GeneralCompare.class

bin/sandbox/TestLambdas.class

bin/search/DepthFirstSearch.class

bin/search/GeneralCompare.class

bin/search/Node.class

bin/search/RedBlackTree.class

bin/sort/GeneralCompare.class

bin/sort/MergeSort.class

src/search/Field.java

src/search/Node.java

src/search/RedBlackTree.java