Concrete comparison is done by method compare(Node* const &, Node* const &)
LexicographicalComparator : A Comparator which stores a vector of Comparators and which performs lexicographical comparison
-IntComparator : Compares the values of a given Attribute of the Nodes which is decoded as an int value
-FloatComparator : Compares the values of a given Attribute of the Nodes which is decoded as a float value
-StringComparator : Compares the values of a given Attribute of the Nodes which is decoded as a string value
+IntComparator : Compares the values of a given Attribute of the Nodes which is decoded as an int value
+FloatComparator : Compares the values of a given Attribute of the Nodes which is decoded as a float value
+StringComparator : Compares the values of a given Attribute of the Nodes which is decoded as a string value
* Models : TreeHandler and descendants