Budget Chatbot Core Code - attached to a budget Google Spreadsheet - based on API.AI with Facebook Messenger + Heroku Integration

Webhook service that gets Api.ai classification JSON, possibly applies some processing involving a budget Google Spreadsheet, and returns a fulfillment response.

When integrated with Facebook Messenger, this can lead to interactions such as this simple example:

human: how much have I spent this month?
bluebot: $2,010

human: how many days left in the budget month?
bluebot: 10 days left in budget month including today.

https://heroku.com/deploy

Certain files are excluded for privacy reasons, but core code is all included.

Intended to run on Python 3.