Revert "Removed a comment"

This reverts commit fcdffb5c1006d7938d8be4aacad7ec5a7b78f20e.

utilities/utils.go

@@ -2,6 +2,11 @@ package utilities
 
 import "errors"
 
+/*
+The Pair and PairList have been taken from google groups forum,
+https://groups.google.com/forum/#!topic/golang-nuts/FT7cjmcL7gw
+*/
+
 // Utility struct that helps in sorting the available power by value.
 type Pair struct {
 	Key   string