deepEqual implementation issue

There is a problem with the implementation of deepEqual.
`deepEqual(["A","B"],["A","B","C"])` returns true, which it should not.

From my testing, this is a problem because the algorithm only tests if "objA" has properties that "objB" doesn't have and not if "objB" has properties that "objA" doesn't have. So if "objB" is a superset of "objA", deepEqual evaluates correctly.
