Uses the recommended rules apart from complexity/useArrowFunction,
which would affect about 1700 lines of code with little benefit
right now. This is something that can be addressed over time.
Reduce production (sub)depedency count from 93 to 50.
Modernise dev tooling, e.g. use nyc, replace jshint with semistandard.
Make 'npm test' command consistent across platforms.