Simple switch and sonar tests

I've done some simple shape tests for switch and sonar. I thought I would be able to add events to sonar but to no avail. I thought it would be the same as ping but for some reason the sonar object instance doesn't detect data events.

Anyway once again I guess these skeletons are better than nothing , not sure if you want to merge now or wait for me to delve deeper when I have time.

https://github.com/rwaldron/johnny-five/issues/205
https://github.com/rwaldron/johnny-five/issues/206