As an enhancement to https://github.com/localstack/localstack/pull/1194

It would be really helpful to send the Lambda name, either as data, a header, or as part of the URL.

At code location: https://github.com/localstack/localstack/blob/03c6f4bf250edd18eb818ed65090f508636b0bff/localstack/services/awslambda/lambda_api.py#L696

I can likely open a PR to handle this given some feedback on the feature and potential design.

Right now all I see is the following (using `npx http-echo-server`):
```
[socket#8] event: data
--> POST / HTTP/1.1
--> Host: 192.168.1.x:3000
--> User-Agent: python-requests/2.22.0
--> Accept-Encoding: gzip, deflate
--> Accept: */*
--> Connection: keep-alive
--> Content-Length: 9
--> Content-Type: application/x-www-form-urlencoded
-->
-->
[socket#8] event: data
--> Name=test
```
expected.append('.*Lambda log message - logging module')
        self.check_lambda_logs(lambda_name, expected_lines=expected)
        
        testutil.delete_lambda_function(lambda_name)
    def test_upload_lambda_from_s3(self):
        lambda_name = 'test_lambda_%s' % short_uid()
        bucket_name = 'test-bucket-lambda'
        bucket_key = 'test_lambda.zip'
        
        zip_file = testutil.create_lambda_archive(
            load_file(TEST_LAMBDA_PYTHON), get_content=True,
            libs=TEST_LAMBDA_LIBS, runtime=LAMBDA_RUNTIME_PYTHON27)
        self.s3_client.create_bucket(Bucket=bucket_name)
        self.s3_client.upload_fileobj(
            BytesIO(zip_file), bucket_name, bucket_key)
        
        self.lambda_client.create_function(
            FunctionName=lambda_name, Handler='handler.handler',
            Runtime=lambda_api.LAMBDA_RUNTIME_PYTHON27, Role='r1',
            Code={
                'S3Bucket': bucket_name,
                'S3Key': bucket_key
            }
        )
        
        data_before = b'{"foo": "bar with \'quotes\\""}'
        result = self.lambda_client.invoke(
            FunctionName=lambda_name, Payload=data_before)
        data_after = json.loads(result['Payload'].read())
        self.assertEqual(json.loads(to_str(data_before)), data_after['event'])