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```

if inner_item:
                        existing_items.append(find_existing_item(inner_item))
            ProxyListenerDynamoDB.thread_local.existing_items = existing_items
        elif action == '%s.UpdateTimeToLive' % ACTION_PREFIX:
            
            response = Response()
            response.status_code = 200
            self._table_ttl_map[data['TableName']] = {
                'AttributeName': data['TimeToLiveSpecification']['AttributeName'],
                'Status': data['TimeToLiveSpecification']['Enabled']
            }
            response._content = json.dumps({'TimeToLiveSpecification': data['TimeToLiveSpecification']})
            fix_headers_for_updated_response(response)
            return response
        elif action == '%s.DescribeTimeToLive' % ACTION_PREFIX:
            response = Response()
            response.status_code = 200
            if data['TableName'] in self._table_ttl_map:
                if self._table_ttl_map[data['TableName']]['Status']:
                    ttl_status = 'ENABLED'
                else:
                    ttl_status = 'DISABLED'
                response._content = json.dumps({
                    'TimeToLiveDescription': {
                        'AttributeName': self._table_ttl_map[data['TableName']]['AttributeName'],
                        'TimeToLiveStatus': ttl_status
                    }
                })
            else:  
                response._content = json.dumps({'TimeToLiveDescription': {'TimeToLiveStatus': 'DISABLED'}})