Add tests to project

[jhartwell]

Currently there are no tests and that is a problem as we are relying on contributors to set up their database and test. Now, connecting to a database is going to be difficult to test as well as the query but the output is easy to test using mocks.

[sashman]

@jhartwell I can give you a hand with this if you don't mind?

[jhartwell]

@sashman knock yourself out. It would be nice to have several SQL files that will allow somebody to easily populate the database with the test data in order to run the test suite

[sashman]

@jhartwell any thoughts on #107 ?

[jhartwell]

@sashman , sorry for the delay. That PR looks good. Please rebase with master and open a non-draft PR. Thanks for your help!