New solution of problem : BinaryTreeLevelOrderTraversal.
  Language : C++.
 New solution of problem : BinaryTreeLevelOrderTraversal.
 Update version of recursive solution.
 Language : C++.
 New solution of problem : BinaryTreeLevelOrderTraversal.
 Methord 2nd : recursive.
 Language : C++.
Merge branch 'master' of https://github.com/lewsn2008/leetcode