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
```
version = version or '$LATEST'
    func_version = func_details.get_version(version)
    result = {
        'CodeSha256': func_version.get('CodeSha256'),
        'Role': func_details.role,
        'Version': version,
        'FunctionArn': func_details.arn(),
        'FunctionName': func_details.name(),
        'CodeSize': func_version.get('CodeSize'),
        'Handler': func_details.handler,
        'Runtime': func_details.runtime,
        'Timeout': func_details.timeout,
        'Description': func_details.description,
        'MemorySize': func_details.memory_size,
        'LastModified': func_details.last_modified,
        'TracingConfig': {'Mode': 'PassThrough'},
        'RevisionId': func_version.get('RevisionId'),
        'State': 'Active',
        'LastUpdateStatus': 'Successful'
    }
    if func_details.dead_letter_config:
        result['DeadLetterConfig'] = func_details.dead_letter_config
    if func_details.envvars:
        result['Environment'] = {
            'Variables': func_details.envvars
        }
    if (always_add_version or version != '$LATEST') and len(result['FunctionArn'].split(':')) <= 7:
        result['FunctionArn'] += ':%s' % version
    return result
def forward_to_fallback_url(func_arn, data):