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
```
arn = func_arn(function)
    data = json.loads(request.data)
    lambda_details = arn_to_lambda.get(arn)
    if not lambda_details:
        return not_found_error(arn)
    lambda_details.concurrency = data
    return jsonify(data)
@app.route('/<version>/tags/<arn>', methods=['GET'])
def list_tags(version, arn):
    func_details = arn_to_lambda.get(arn)
    if not func_details:
        return not_found_error(arn)
    result = {'Tags': func_details.tags}
    return jsonify(result)
@app.route('/<version>/tags/<arn>', methods=['POST'])
def tag_resource(version, arn):
    data = json.loads(request.data)
    tags = data.get('Tags', {})
    if tags:
        func_details = arn_to_lambda.get(arn)
        if not func_details:
            return not_found_error(arn)
        if func_details:
            func_details.tags.update(tags)
    return jsonify({})
@app.route('/<version>/tags/<arn>', methods=['DELETE'])
def untag_resource(version, arn):
    tag_keys = request.args.getlist('tagKeys')
    func_details = arn_to_lambda.get(arn)
    if not func_details: