Update Everything (almost)

[zwrawr]

closes #123 (since it has merge issues)

Changes

.travis.yml

updated to current + LTS versions see https://nodejs.org/en/about/releases/

package.json

Updated all dependencies to the latest version. Except istanbul and readdirp. Istanbul was deprecated and the new version is called NYC. I didn't swap it out as I cannot see it being used anywhere. ReadDirP was updated to the newest 2.x version. It wasn't updated to 3.x because the callback API was deprecated. A separate pull request to update the code to use promises or streams is needed.

src/sloc.coffee

Wrapped a line because the linter was complaining.

Tests

two tests fail, but they seem to fail in master aswell 2) should support agda 1) should support rpy

travis fails #127 due to the two errors above