First implementation of tokenized infix expression evaluator.
Merge github.com:ghortiz-pena/CS-122

Conflicts:
	Token-Infix/driver.cpp
	Token-Infix/evaluate
	Token-Infix/evaluate.cpp
	Token-Infix/evaluate.h
	Token-Infix/token.cpp
	Token-Infix/token.h
	Token-Infix/tokenlist.cpp
	Token-Infix/tokenlist.h