runtime.py : python library forwarding done consistently now
chaos.n : demo to show chaos examples
EZTurtle.py : add setworldcoordinates method
ezhil_parser.py : add left associativity for - operator
ezhil_scanner.py : add token for always breaking - as a symbol, numbers are always their own token
fact.n : add assertion tests and function arg w/ compound expressions
prime.n, test: add prime number finding test