#5: add class-definitions.py file to contain all logic-component classes
#5: rename class-definitions.py -> class_definitions.py
#5: rename class-definitions.py -> class_definitions.py
#5: change corresponding comment to reflect file name
#5: import class definitions, and use the 'Node()' class
#5: rename least-common-ancestor.py -> least_common_ancestor.py
#5: change comment to reflect changed filename
#5: add method to insert node to tree (class_definitions.py)
#5: reformat file with 2-space indentation standard (class_definitions.py)
#5: recursive breadth-first print
#5: properly call class methods to build tree
#5: add the necessary Node class methods for commit 9443288 (above)
Merge pull request #7 from jeff1evesque/create-btree-for-algorithm

#5: create binary search tree representation in 'least_common_child.py'