Write a method that reverses sections of a string. The sections to be reversed will be 'len' long starting at the beginning of the string. For example, the string "reverse" with 'len' having a value of 3 would result in "versree". The reason for this is that the string would be broken into sections that are three characters long such as "rev", "ers", and "e" then each of those sections would be reversed to become "ver", "sre" and "e" then reassembled to make "versree". You do NOT have to follow that exact process as long as your result is the same. This can be done with or without recursion. The only string methods you are allowed to use are .length, .equals, .charAt, and .substring. Look at the test data for additional examples.