text: Title: API Endpoint /represent fails with 400 for array of img URLs
  Body: ### Description
  
  Using an array of `img` items via the API endpoint `represent` responds with the following error
  
  ```
  {
      "error": "Exception while representing: img must be numpy array or str but it is <class 'list'>"
  }
   ```
  
  #### Steps to Reproduce
  1. Pull repo
  
  2. Build the image
  `docker build -t deepface -f Dockerfile .`
  
  3. Run the image
  `docker run deepface`
  
  4. Attempt to use the represent endpoint with an array of images i.e.:
  
  ```
  {
      "img": ["imgUrl1", "imgUrl2"]
  }
  ```
  
  ### Expected Behavior
  
  The API is able to parse the list into a numpy array and completed the request.