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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description
When `mountCode: true` for a serverless.yml deployment to localstack on Windows, Localstack mounts the wrong path.
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## Expected behavior
Docker expects the Windows client path value of the `-v` flag to begin with `/host_mtn/`.
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## Actual behavior
Localstack does not add this to the Windows client path. This causes the volume sharing to fail. Once one tries to invoke a lambda without the proper volume sharing, the lambda fails with an error along the lines of "can't find no module 'lambda_name'".
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# Steps to reproduce
1. In your `serverless.yml` set `mountCode: true` 
2. In your `docker-compose.yml` set the environment variable `LAMBDA_REMOTE_DOCKER: "0"` for the localstack container
3. Deploy some test lambda to the localstack container
4. Attempt to invoke with `awslocal lambda invoke --function-name LAMBDA_NAME out.txt` and replace LAMBDA_NAME with the name of your test lambda.
5. Note the invocation failure.

## Command used to start LocalStack
Started via a `docker-compose.yml` file. Pretty basic stuff.
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## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)
Just the `awslocal` invoke command outlined above.
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import re
import os
import socket
import logging
import platform
import tempfile
import subprocess
from os.path import expanduser
import six
from boto3 import Session
from localstack.constants import (
    DEFAULT_SERVICE_PORTS, LOCALHOST, DEFAULT_PORT_WEB_UI, TRUE_STRINGS, FALSE_STRINGS,
    DEFAULT_LAMBDA_CONTAINER_REGISTRY, DEFAULT_PORT_EDGE)
LAMBDA_JAVA_OPTS = os.environ.get('LAMBDA_JAVA_OPTS', '').strip()
KINESIS_SHARD_LIMIT = os.environ.get('KINESIS_SHARD_LIMIT', '').strip() or '100'
KINESIS_LATENCY = os.environ.get('KINESIS_LATENCY', '').strip() or '500'
if 'DEFAULT_REGION' not in os.environ:
    os.environ['DEFAULT_REGION'] = 'us-east-1'
DEFAULT_REGION = os.environ['DEFAULT_REGION']
KINESIS_ERROR_PROBABILITY = float(os.environ.get('KINESIS_ERROR_PROBABILITY', '').strip() or 0.0)
DYNAMODB_ERROR_PROBABILITY = float(os.environ.get('DYNAMODB_ERROR_PROBABILITY', '').strip() or 0.0)
HOSTNAME = os.environ.get('HOSTNAME', '').strip() or LOCALHOST
HOSTNAME_EXTERNAL = os.environ.get('HOSTNAME_EXTERNAL', '').strip() or LOCALHOST
SQS_PORT_EXTERNAL = int(os.environ.get('SQS_PORT_EXTERNAL') or 0)
LOCALSTACK_HOSTNAME = os.environ.get('LOCALSTACK_HOSTNAME', '').strip() or HOSTNAME
LAMBDA_REMOTE_DOCKER = os.environ.get('LAMBDA_REMOTE_DOCKER', '').lower().strip() in TRUE_STRINGS
LAMBDA_DOCKER_NETWORK = os.environ.get('LAMBDA_DOCKER_NETWORK', '').strip()
LAMBDA_CONTAINER_REGISTRY = os.environ.get('LAMBDA_CONTAINER_REGISTRY', '').strip() or DEFAULT_LAMBDA_CONTAINER_REGISTRY
LAMBDA_REMOVE_CONTAINERS = os.environ.get('LAMBDA_REMOVE_CONTAINERS', '').lower().strip() not in FALSE_STRINGS