Complete tests for smpl.data.js

This file has now 100% coverage
New command `npm run-script unit`

Allow to run unit test without JSHINT.
Unit tests now use a minimal reporter when run from `npm test` and the
full reporter when run from the new command
Run unit test against the src directory

We don't need to run npm install anytime we change source. npm test will
always use the latest files
Get more accurate code coverage.

Code coverage is now also including files with no unit test.
The unit tests are requiring the full library.