Write a method called flipMap that accepts a Map that maps from Strings to Integers. Your method should create and return a new map where the keys and values are flipped. If there are two different keys that map to the same value, your resulting map should have one key that maps to those two values. For example, if a map were passed in with keys and values as follows: {hi=5, aloha=7, howdy=4, hello=9, hola=5}, then the resulting map that should be created and return would be: {4=[howdy], 5=[hi, hola], 7=[aloha], 9=[hello]}.