Write comprehensive tests

[phdavis1027]

This encompasses:

1. Unit tests, mostly for serialization/deserialization logic, which should be fairly easy to encapsulate in each struct's respective file.
2. Integration tests, which will require starting then cleaning up a (probably dockerized) zone. I have been using the --leak-container flag of the iRODS Testing Environment to manually check for correct behavior during development, but this could and should be automate.
3. Ideally, put all of this into CI