Apply CC BY-NC-SA 4.0 and Apache 2.0 licenses.

Preview: 

![Licensing Preview](https://www.evernote.com/shard/s226/sh/140b9f9f-32c5-4d98-a0f6-b7e9bcd2a8a2/0413092972b4729dffe4eff385cb06c2/deep/0/meos-licensing.png)

I'm planning on adding a *Credits and Licensing* section soon which will list Mick and April as authors and maintainers. It will also explain the rationale for the licenses and explain any exceptions. Following the lead of other projects, I'd like to keep the copyright under the original authors, Sean and Ira.