LintCode-171.Anagrams [http://www.lintcode.com/en/problem/anagrams/]
> Given an array of strings, return all groups of strings that are anagrams.
> Notice: All inputs will be in lower-case.
> Example
> Given ["lint", "intl", "inlt", "code"], return ["lint", "inlt", "intl"].
> Given ["ab", "ba", "cd", "dc", "e"], return ["ab", "ba", "cd", "dc"