value_counts: name and index'es name
Good day!

```python
s = pd.Series(np.arange(10), name='items')
c = s.value_counts()

c.name  #=> 'items'

c.index.names  #=> None
```

IMHO that's very strange. Values of `c` are quantities/counts/etc. not "items". "Items" are represented in `c.index`. No?

What do you think?

Thanks!