add arrays.fromPairs method, tests, docs

[jkvyff]

Ref: #58

[evanplaice]

Damn you're killin' it. 👍

I've been a bit under the weather but I'll try to get all these PRs reviewed/merged by tomorrow.

[jkvyff]

No worries, it is just nice to make consistent progress on open source as I job hunt.

[evanplaice]

I hear ya, it's good to stay sharp. BTW, good job on that DevTo article about setting up a remote tracking branch. That's usually a pretty tough concept to grasp for new OSS contributors.

On a positive note, this project is finally starting to gain some traction.

I may drop the pretext about this project being mostly useless. TBH, this project was created as a testing ground for nodejs/modules. I was trying to discourage users from using this in prod until after ES modules gain full support.