Housekeeping upgrades

[matthewliuswims]

👋 @weswigham thank you for your work :) this repo rocks! LMK if I need to make changes for this PR, and I'll be happy to make 'em

What

• made config upgrades for the javascript and typescript repos with 2 corresponding commits. javascript here and typescript here
• basically bumped versions of webpack, react and babel to modern versions with appropriate README changes

Why

• webpack4, react16, and babel7 have been out for a while now and are the modern package versions. the typescript docs from what I've seen assumes those versions. so this PR is creating parity with the docs and with what many people probably have as dependency versions

How I tested

• manually done and reproduced README steps. a quick sanity check one can do is npm install && npx webpack within the JS and typescript repo and open up index.html for each repo and verify everything was working

Miscellaneous

• awesome-typescript-loader --> ts-loader....is because awesome-typescript-loader is deprecated while ts-loader is recommended throughout many of the docs

[msftclas]

All CLA requirements met.

[orta]

Hi! Thanks for the detailed write-up, yeah, these changes look great to me - let's get them in.