Started with `localstack start` then navigated to `http://localhost:4569/shell`

Localstack version is `0.10.5`

![Screenshot from 2019-11-26 08-15-03](https://user-images.githubusercontent.com/57932946/69588919-24798700-1025-11ea-94d2-9cfb6dd20004.png)

Console log below, its all the same so I am just posting one

```2019-11-26T00:13:18:ERROR:localstack.services.generic_proxy: Error forwarding request: the JSON object must be str, bytes or bytearray, not NoneType Traceback (most recent call last):
  File "/opt/code/localstack/localstack/services/generic_proxy.py", line 240, in forward
    path=path, data=data, headers=forward_headers)
  File "/opt/code/localstack/localstack/services/dynamodb/dynamodb_listener.py", line 44, in forward_request
    data = json.loads(to_str(data))
  File "/usr/lib/python3.7/json/__init__.py", line 341, in loads
    raise TypeError(f'the JSON object must be str, bytes or bytearray, '
TypeError: the JSON object must be str, bytes or bytearray, not NoneType```

stream = data['StreamSpecification']
    enabled = stream.get('StreamEnabled')
    if enabled not in [False, 'False']:
        table_name = data['TableName']
        view_type = stream['StreamViewType']
        dynamodbstreams_api.add_dynamodb_stream(table_name=table_name,
            latest_stream_label=latest_stream_label, view_type=view_type, enabled=enabled)
def forward_to_lambda(records):
    for record in records:
        sources = lambda_api.get_event_sources(source_arn=record['eventSourceARN'])
        event = {
            'Records': [record]
        }
        for src in sources:
            lambda_api.run_lambda(event=event, context={}, func_arn=src['FunctionArn'])
def forward_to_ddb_stream(records):
    dynamodbstreams_api.forward_events(records)
def dynamodb_extract_keys(item, table_name):
    result = {}
    if table_name not in TABLE_DEFINITIONS:
        LOGGER.warning('Unknown table: %s not found in %s' % (table_name, TABLE_DEFINITIONS))
        return None
    for key in TABLE_DEFINITIONS[table_name]['KeySchema']:
        attr_name = key['AttributeName']
        if attr_name not in item:
            return error_response(error_type='ValidationException',
                message='One of the required keys was not given a value')
        result[attr_name] = item[attr_name]
    return result
def error_response(message=None, error_type=None, code=400):