1.Implemented loops for operations in Operations.class and
LazyTree.class using arrays which increased speed.
2.Implemented clone() in children of Dataset.class to pass the reference
of the actual data, not cloning it wasting memory.
3.Implemented new "main" loop which is faster than the nested for loops.
4.Implemented several testing methods to compare speeds between
different versions of "applyOp()" in "Operations.class".