index bug in 0.14?
```
pandas.Index([('a',), ('a', 'b')]).values
```

pandas < 0.14 returns:

```
array([('a',), ('a', 'b')], dtype=object)
```

pandas 0.14 returns:

```
array([('a', nan), ('a', 'b')], dtype=object)
```

possibly related to https://github.com/pydata/pandas/issues/7548 ?
