Update README file - Extend explanations, fix formatting mistakes and expand examples

[bstashchuk]

I am author of few JavaScript courses on Udemy.
While recording new JavaScript course I used AirBnb Style Guide in one of the sections and noticed few ways for improvements.

• Expanded examples
• Fixed some formatting mistakes
• Extended explanations

[bstashchuk]

Thanks for the quick feedback @ljharb
I hope we will be able to incorporate few of my changes.

[bstashchuk]

@ljharb I am still thinking about 19.6

There are actually general ESLint rules regarding method chains formatting but for some reason all examples are about jQuery and DOM manipulation.

No pure JS examples of methods chaining for arrays or some objects manipulation.

May I reduce quantity of the jQuery examples (or make them less confusing due to the long chains of method calls with different indents) and add some additional examples with bad/good formatting?

[bstashchuk]

Hi @ljharb ,
let me know if something else is needed to change in this PR.
It seems all questions were resolved.
Bogdan