json normalize max level not working
#### Code Sample, a copy-pastable example if possible

```python
from pandas.io.json import json_normalize

data = [{'id': 1,
          'name': "Cole Volk",
          'fitness': {'height': 130, 'weight': 60}},
         {'name': "Mose Reg",
          'fitness': {'height': 130, 'weight': 60}},
        {'id': 2, 'name': 'Faye Raker',
          'fitness': {'height': 130, 'weight': 60}}]
json_normalize(data, max_level=0)
```
#### Problem description

The code above is from the pandas docs. I'm running python 3.6.4 and pandas==0.22.0


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#### Expected Output

#### Output of ``pd.show_versions()``

<details>

[paste the output of ``pd.show_versions()`` here below this line]

</details>
