CLN: Make ufunc works for Index
closes #9966, #9974 (PR)

I understand these are never used because `Index` is no longer the subclass of `np.array`. Correct?
- [x] Add tests for ~~all~~ almost ufuncs
  - http://docs.scipy.org/doc/numpy/reference/ufuncs.html
- ~~CategoricalIndex~~: Needs to be done separately to fix `Categorical`, because number of categories can be changed.

```
np.sin(pd.Categorical([1, 2, 3]))
array([ 0.84147098,  0.90929743,  0.14112001])
```
- [x] MultiIndex: Raise `TypeError` or `AttributeError`, as ufuncs are performed to array of tuples.
