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
```
log_events = LambdaTestBase.get_lambda_logs(func_name)
        log_messages = [e['message'] for e in log_events]
        for line in expected_lines:
            if '.*' in line:
                found = [re.match(line, m) for m in log_messages]
                if any(found):
                    continue
            self.assertIn(line, log_messages)
    @staticmethod
    def get_lambda_logs(func_name):
        logs_client = aws_stack.connect_to_service('logs')
        log_group_name = '/aws/lambda/%s' % func_name
        streams = logs_client.describe_log_streams(logGroupName=log_group_name)['logStreams']
        streams = sorted(streams, key=lambda x: x['creationTime'], reverse=True)
        log_events = logs_client.get_log_events(
            logGroupName=log_group_name, logStreamName=streams[0]['logStreamName'])['events']
        return log_events
class TestLambdaBaseFeatures(unittest.TestCase):
    def test_forward_to_fallback_url_dynamodb(self):
        db_table = 'lambda-records'
        ddb_client = aws_stack.connect_to_service('dynamodb')
        def num_items():
            return len((run_safe(ddb_client.scan, TableName=db_table) or {'Items': []})['Items'])
        items_before = num_items()
        _run_forward_to_fallback_url('dynamodb://%s' % db_table)
        items_after = num_items()
        self.assertEqual(items_after, items_before + 3)
    def test_forward_to_fallback_url_http(self):
        class MyUpdateListener(ProxyListener):
            def forward_request(self, method, path, data, headers):