After cloning the repo and running: `docker build -t localstack:latest .`
I can see the following errors:

```
Starting mock Lambda service (http port 4574)...
ERROR: Error forwarding request: HTTPConnectionPool(host='127.0.0.1', port=4564): Max retries exceeded with url: / (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7f4c7b4e7c10>: Failed to establish a new connection: [Errno 111] Connection refused',)) Traceback (most recent call last):
  File "/opt/code/localstack/localstack/services/generic_proxy.py", line 216, in forward
    headers=forward_headers, stream=True)
  File "/opt/code/localstack/.venv/lib/python2.7/site-packages/requests/api.py", line 116, in post
    return request('post', url, data=data, json=json, **kwargs)
  File "/opt/code/localstack/.venv/lib/python2.7/site-packages/requests/api.py", line 60, in request
    return session.request(method=method, url=url, **kwargs)
  File "/opt/code/localstack/.venv/lib/python2.7/site-packages/requests/sessions.py", line 524, in request
    resp = self.send(prep, **send_kwargs)
  File "/opt/code/localstack/.venv/lib/python2.7/site-packages/requests/sessions.py", line 637, in send
    r = adapter.send(request, **kwargs)
  File "/opt/code/localstack/.venv/lib/python2.7/site-packages/requests/adapters.py", line 516, in send
    raise ConnectionError(e, request=request)
ConnectionError: HTTPConnectionPool(host='127.0.0.1', port=4564): Max retries exceeded with url: / (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7f4c7b4e7c10>: Failed to establish a new connection: [Errno 111] Connection refused',))
```

I see the same thing when running `localstack start --docker` which is what I originally tried as I would like to use localstack for development purposes in an existing stack.

MacOS Mojave 10.14
Docker for Mac: 18.06.1-ce-mac73 (26764)
def publish_lambda_duration(time_before, kwargs):
    time_after = now_utc()
    publish_lambda_metric('Duration', time_after - time_before, kwargs)
def publish_lambda_error(time_before, kwargs):
    publish_lambda_metric('Invocations', 1, kwargs)
    publish_lambda_metric('Errors', 1, kwargs)
def publish_lambda_result(time_before, result, kwargs):
    if isinstance(result, Response) and result.status_code >= 400:
        return publish_lambda_error(time_before, kwargs)
    publish_lambda_metric('Invocations', 1, kwargs)
def get_metric_statistics(Namespace, MetricName, Dimensions,
        Period=60, StartTime=None, EndTime=None, Statistics=None):
    if not StartTime:
        StartTime = datetime.now() - timedelta(minutes=5)
    if not EndTime:
        EndTime = datetime.now()
    if Statistics is None:
        Statistics = ['Sum']
    cloudwatch_url = aws_stack.get_local_service_url('cloudwatch')
    url = '%s/?Action=GetMetricValues' % cloudwatch_url
    all_metrics = make_http_request(url)
    assert all_metrics.status_code == 200
    datapoints = []
    for datapoint in json.loads(to_str(all_metrics.content)):
        if datapoint['Namespace'] == Namespace and datapoint['Name'] == MetricName:
            dp_dimensions = datapoint['Dimensions']
            all_present = all(m in dp_dimensions for m in Dimensions)
            no_additional = all(m in Dimensions for m in dp_dimensions)
            if all_present and no_additional:
                datapoints.append(datapoint)