Cleanup (for #2)

[jferragut]

Addresses the following issues related to #2

• cleaned up some files that were causing issue with boilerplate
• modified user endpoint to show example of firebase firestore for data storage
• added model.py to show how we inherit from a base class that we create to represent our data
• added example of .env and key.json which are required for the firebase endpoint
• added dependencies to pipfile
• adjusted scripts in pipfile for zeit instead of flask local dev for a more accurate dev server
• updated git ignore to include the key.json file so you don't accidentally push your google credentials to repo

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[jferragut]

@alesanchezr when you have a moment, can you please review this PR