Set up our testing framework and one test

[ashryanbeats]

This is wide open, but still could be a good first issue for someone who feels confident in testing and wants to help us get on good footing with testing. We'd love to have tests for both our Node.js backend and our React frontend.

If someone takes this on, it would be good to start splitting this out a bit from a monolithic "Write tests" issue :)

[ashryanbeats]

Options:

• Jest, enzyme
• Mocha, chai

What are we testing?

Server

• Getting data
• Storing data
• Accessing data

Front end

• After a call to server, I can get this data