Final version of sortTest
Added Queue and Stack interface. Completet SortTest
added Queue and Stack interfaces and class MyStack
added MyQueue (uncomplete)
MyQueue complete
MyLinkedList added (uncomplete)
added castToLNode Method
added Tree interface
added MyTree
Completed MyLinkedList and changed MyTree
added some methods to MyTree
added a heapSort method (uncomplete) to SortTest
aded  heapSort (uncomplete) to SortTest.
added Locator and PriorityQueue
added uncomplete MyPriorityQueue