Hello all,

I have noticed that when I generate a presigned url for a file that will be uploaded to S3 that the Lambda function does not get triggered. It seems to only be happening for presigned url. I was able to successful have it trigger when I use the command line and upload a file through `aws s3 cp`. 

To recreate:
1: have any lambda function be added to an s3 bucket. My lambda configurations look as followed:
```
aws s3api --endpoint-url=http://localstack:4572 create-bucket --bucket mybucket;
aws s3api --endpoint-url=http://localstack:4572 create-bucket --bucket code;
aws s3 cp --endpoint-url=http://localstack:4572 --acl public-read /resources/example.zip s3://code/;
aws lambda create-function --endpoint-url=http://localstack:4574 --function-name MyLambdaFunction--runtime 'nodejs8.10' --handler 'index.handler' --role 'anyRole' --code S3Bucket=code,S3Key=example.zip,S3ObjectVersion=1.0.0;
```
Then add this lambda configuration to the bucket
```
{
    "LambdaFunctionConfigurations": [
        {
            "LambdaFunctionArn": "arn:aws:lambda:us-east-1:000000000000:function:MyLambdaFunction",
            "Events": [
                "s3:ObjectCreated:*"
            ]
        }
    ]
}
```
by running
```
aws s3api --endpoint-url=http://localstack:4572 put-bucket-notification-configuration --bucket 'mybucket' --notification-configuration file:///resources/notification.json;
```
2: Generate a presigned url for the bucket you added the lambda too

```
aws s3 presign --endpoint-url=http://localstack:4572 s3://mybucket/test.txt  --expires-in 300
```
3:
```
 curl --upload-file test.txt -v http://localstack:4572/mybucket/test.txt?AWSAccess
KeyId=dummyaccess&Expires=1571680684&Signature=TbCFh1rzkNYwNEooaQKcJPF4%2Fss%3D
```

Lambda does not seem to get triggered.

Any help or fixes?

Thank you so much for your time and help. Localstack has been a great tool!
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                port_mappings += ' -p {port}:{port}'.format(port=port)
    env_str = ''
    for env_var in config.CONFIG_ENV_VARS:
        value = os.environ.get(env_var, None)
        if value is not None:
            env_str += '-e %s="%s" ' % (env_var, value)
    data_dir_mount = ''
    data_dir = os.environ.get('DATA_DIR', None)
    if data_dir is not None:
        container_data_dir = '/tmp/localstack_data'
        data_dir_mount = '-v "%s:%s"' % (data_dir, container_data_dir)
        env_str += '-e DATA_DIR="%s" ' % container_data_dir
    interactive = '' if force_noninteractive or in_ci() else '-it '
    
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    entrypoint = '%s ' % entrypoint if entrypoint else entrypoint
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    web_ui_flags = ''
    if config.START_WEB:
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            config.DOCKER_CMD, interactive, entrypoint, env_str, user_flags, plugin_run_params,