Part 4: Updated comment headers and fixed dependency for branch.cpp and branch.h
Part 4: Updated comment headers for tree.cpp and tree.h
Minor whitespace fix in part 3
Part 4: Updated comment headers for fileparser.cpp and fileparser.h
Part 4: Updated comment headers for interface.cpp and interface.h
Part 4: Imported changes from part 3
Part 4: Implemented disk address lookups for articles, titles, authors, abstracts, words, and now furnishes an interface to interact with each article for a searched word