removed underscore as a dependency

[dydx]

Not that this is really a huge deal, but it was fairly straight forward. Zero dependencies now!

My update does require node >= 6.x.x. If there are requirements for using more legacy versions, I could pretty easily get that going as well, just a few syntax changes.

[kaue]

@dydx Thanks for the PR 👍

Travis is showing some errors with Node v5 / v4 any ideas?

I think would be better to move helpers.js to core/helper.js

[dydx]

As mentioned in the PR, those are just syntactical things (destructuring and arrow syntax). Relatively easy to downgrade.

And yeah, moving code to 'core/helper.js' can be accomplished.

[kaue]

@dydx Thanks for the help =) looks good to merge.

[dydx]

OK. Moved lib/helpers.js into lib/core/helper.js and removed the object destructuring; e.g. const { isArray } = require('./helpers.js');

Travis is happy now!

[kaue]

@dydx I just published v2.0.7 to npm.

Thanks again! feel free to submit other PR if you have any idea.

[kaue]

@dydx We could make the lib even smaller by creating the data.json in benchmark.js since its a 10mb file.

[kaue]

Maybe its better to just use https://docs.npmjs.com/misc/developers#keeping-files-out-of-your-package to ignore the benchmark folder