Add specs

[xrd]

I want to add specs to this using the karma test runner.

I am unclear as to how we should test it.

Can any of you help: @glebm, @sectore, @johnb-razoo, @alanramsay, @Dorian?

I've created a branch called add_specs. There is one test in there but it is broken. If you are willing to pull the latest version of the repo and run karma from within that branch, I would be happy to see someone figure out how to get this working.

[xrd]

Just run these commands:

$ npm install karma -g
$ karma start karma-conf.js