text: Title: [Migrated] No module named 'app': ModuleNotFoundError , slim_handler : true
  Body: Originally from: https://github.com/Miserlou/Zappa/issues/1482 by [houdinisparks](https://github.com/houdinisparks)
  
  <!--- Provide a general summary of the issue in the Title above -->
  ## Context
  I am trying to deploy a >100 mb flask app with slim_handler : true. Below is my file structure:
  
  ```
  +-- app
  |   +-- routes
  |   +-- static
  |   +-- __init__.py
  |   +-- load.py
  +-- venv
  +-- run.py
  +-- setup.py
  +-- requirements.txt
  ```
  However, when i try to deploy to zappa, its gives me the following error below:
  ```
  No module named 'app': ModuleNotFoundError
  Traceback (most recent call last):
  File "/var/task/handler.py", line 566, in lambda_handler
  return LambdaHandler.lambda_handler(event, context)
  File "/var/task/handler.py", line 237, in lambda_handler
  handler = cls()
  File "/var/task/handler.py", line 129, in __init__
  self.app_module = importlib.import_module(self.settings.APP_MODULE)
  File "/var/lang/lib/python3.6/importlib/__init__.py", line 126, in import_module
  return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 978, in _gcd_import
  File "<frozen importlib._bootstrap>", line 961, in _find_and_load
  File "<frozen importlib._bootstrap>", line 936, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 205, in _call_with_frames_removed
  File "<frozen importlib._bootstrap>", line 978, in _gcd_import
  File "<frozen importlib._bootstrap>", line 961, in _find_and_load
  File "<frozen importlib._bootstrap>", line 948, in _find_and_load_unlocked
  ModuleNotFoundError: No module named 'app'
  
  ```
  
  this is my zappa_settings.json
  ```
  {
      "dev": {
          "app_function": "run.app",
          "profile_name": "work",
          "project_name": "<projectname>",
          "runtime": "python3.6",
          "s3_bucket": "<s3bucketname>",
          "slim_handler": true
      }
  }
  ```
  
  and my run.py
  ```
  from app.load import create_app
  
  app = create_app()
  
  # We only need this for local development.
  if __name__ == '__main__':
      print("initiating the web app...")
      app.run(debug=True)
  ```
  
  and my load.py file:
  ```
  from flask import Flask
  from app import routes
  
  def create_app():
      """An application factory, as explained here: http://flask.pocoo.org/docs/patterns/appfactories/.
      :param config_object: The configuration object to use.
      """
      app = Flask(__name__, static_url_path='', template_folder="static/pages")
      register_blueprints(app)
      return app
  
  
  
  def register_blueprints(app):
      """Register Flask blueprints."""
      app.register_blueprint(routes.api.api_bp)
      app.register_blueprint(routes.index.webpage_bp)
      return None
  
  ```
  
  
  ## Your Environment
  <!--- Include as many relevant details about the environment you experienced the bug in -->
  * Zappa version used: latest from pip installed from github <0.45.11>
  * Operating System and Python version: Win 10, python 3.6
  * The output of `pip freeze`: 
  ```
  aniso8601==3.0.0
  argcomplete==1.9.3
  asn1crypto==0.24.0
  azure-common==1.1.8
  azure-nspkg==2.0.0
  azure-storage==0.36.0
  base58==0.2.4
  boto3==1.6.4
  botocore==1.9.4
  certifi==2018.1.18
  cffi==1.11.5
  cfn-flip==1.0.0
  chardet==3.0.4
  click==6.7
  -e git+https://wyy95.visualstudio.com/IVAN/_git/ModelDeployment@213574193aa6759d2b7767871714f5c7e3079a11#egg=cognizant
  cryptography==2.2.1
  docutils==0.14
  durationpy==0.5
  Flask==0.12.2
  Flask-REST==1.3
  Flask-RESTful==0.3.6
  future==0.16.0
  hjson==3.0.1
  idna==2.6
  itsdangerous==0.24
  Jinja2==2.10
  jmespath==0.9.3
  kappa==0.6.0
  lambda-packages==0.19.0
  lightgbm==2.1.0
  MarkupSafe==1.0
  numpy==1.14.1
  pandas==0.22.0
  placebo==0.8.1
  pycparser==2.18
  python-dateutil==2.6.1
  python-slugify==1.2.4
  pytz==2018.3
  PyYAML==3.12
  requests==2.18.4
  s3transfer==0.1.13
  scikit-learn==0.19.1
  scipy==1.0.0
  six==1.11.0
  toml==0.9.4
  tqdm==4.19.1
  troposphere==2.2.0
  Unidecode==1.0.22
  urllib3==1.22
  Werkzeug==0.13
  wsgi-request-logger==0.4.6
  zappa==0.45.1
  
  ```
  * Link to your project (optional):
  
  