to_parquet swallows NoCredentialsError
#### Code Sample, a copy-pastable example if possible

```python
try: 
   pd.DataFrame({'foo': [None, ['foo', 'bar']]}).to_parquet('s3://foo/bar') 
except Exception as e: 
   print('Here')                                                                                                                                                                                                            
```
#### Problem description

Without credentials configured, the above code does not write any output, but also doesn't end up in the exception handling code. Instead, on stdout or stderr, an exception is printed:

```
Exception ignored in: <function AbstractBufferedFile.__del__ at 0x7fe0ae8db440>
Traceback (most recent call last):
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/fsspec/spec.py", line 1137, in __del__
    self.close()
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/fsspec/spec.py", line 1114, in close
    self.flush(force=True)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/fsspec/spec.py", line 986, in flush
    self._initiate_upload()
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/s3fs/core.py", line 951, in _initiate_upload
    Bucket=self.bucket, Key=self.key, ACL=self.acl)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/s3fs/core.py", line 939, in _call_s3
    **kwargs)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/s3fs/core.py", line 182, in _call_s3
    return method(**additional_kwargs)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/client.py", line 357, in _api_call
    return self._make_api_call(operation_name, kwargs)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/client.py", line 648, in _make_api_call
    operation_model, request_dict, request_context)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/client.py", line 667, in _make_request
    return self._endpoint.make_request(operation_model, request_dict)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/endpoint.py", line 102, in make_request
    return self._send_request(request_dict, operation_model)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/endpoint.py", line 132, in _send_request
    request = self.create_request(request_dict, operation_model)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/endpoint.py", line 116, in create_request
    operation_name=operation_model.name)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/hooks.py", line 356, in emit
    return self._emitter.emit(aliased_event_name, **kwargs)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/hooks.py", line 228, in emit
    return self._emit(event_name, kwargs)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/hooks.py", line 211, in _emit
    response = handler(**kwargs)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/signers.py", line 90, in handler
    return self.sign(operation_name, request)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/signers.py", line 157, in sign
    auth.add_auth(request)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/auth.py", line 425, in add_auth
    super(S3SigV4Auth, self).add_auth(request)
  File "/home/languitar/.pyenv/versions/analytics-3.7/lib/python3.7/site-packages/botocore/auth.py", line 357, in add_auth
    raise NoCredentialsError
botocore.exceptions.NoCredentialsError: Unable to locate credentials
```

#### Expected Output

`Here`

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

<details>

[paste the output of ``pd.show_versions()`` here below this line]
INSTALLED VERSIONS
------------------
commit           : None
python           : 3.7.4.final.0
python-bits      : 64
OS               : Linux
OS-release       : 4.19.61-1-lts
machine          : x86_64
processor        : 
byteorder        : little
LC_ALL           : None
LANG             : en_US.UTF-8
LOCALE           : en_US.UTF-8

pandas           : 0.25.0
numpy            : 1.17.0
pytz             : 2019.1
dateutil         : 2.8.0
pip              : 19.2.1
setuptools       : 41.0.1
Cython           : None
pytest           : None
hypothesis       : None
sphinx           : None
blosc            : None
feather          : None
xlsxwriter       : 1.1.8
lxml.etree       : None
html5lib         : None
pymysql          : None
psycopg2         : None
jinja2           : 2.10.1
IPython          : 7.7.0
pandas_datareader: None
bs4              : None
bottleneck       : None
fastparquet      : None
gcsfs            : None
lxml.etree       : None
matplotlib       : None
numexpr          : None
odfpy            : None
openpyxl         : None
pandas_gbq       : None
pyarrow          : 0.14.1
pytables         : None
s3fs             : 0.3.1
scipy            : None
sqlalchemy       : None
tables           : None
xarray           : None
xlrd             : None
xlwt             : None
xlsxwriter       : 1.1.8

</details>
