Tests for maintenance mode

Here is a basic test for maintenance mode. Addresses #7. 

I also added a `mocha.opts` file. If you hate that, let me know and I can drop it from the PR. I find it very convenient when you want to just run one or more specific tests as opposed to the whole suite with `make test`. It simply provides the defaults for running the tests (which you can override on the cli if you want), and I set it up to provide the same defaults you have in your recipe for `make test`.