Add unit tests

[dino-rodriguez]

What happened to the unit tests? I noticed the branch is gone.

A lot of those tests were testing balance/account/store logic as well as packet construction very thoroughly. If they are gone, it is very possible that somebody could edit the plugin and cause a minor breaking change (like balance logic not being calculated properly or persisted to the store) and the integration tests would still pass. I feel this could be pretty dangerous considering the plugin is in beta and will have updates.

[kincaidoneil]

The branch had been merged in, so they're all in the commit history for ko-refactor. I do still intend to adapt those unit tests for the updated plugin, but probably not before release.

[dino-rodriguez]

Ok great, that makes sense.