Deploy to Crashlytics Beta on merge to master

[macklinu]

Look into automatically deploying merges to master to the Crashlytics Beta beta users list, which I believe is just @crebma and I right now.

For 1.0.0, I would manually upload builds. I'm over that.

[macklinu]

I didn't upload a build along the way from 1.0.0 to 2.0.0. 😲

I'm thinking about changing the branching strategy up and will make a new issue for it. Essentially:

• develop: the development branch. Pushes to this branch will deploy a debug version of the app to internal testers
• master: the production branch. Pushes to this branch would build the production APK and deploy to the Google Play Store with the help of tools like Fastlane, Google Play Gradle plugins, whatever else.