Standardise code style and remove eslint disables

[ang-zeyu]

What is the purpose of this pull request? (put "X" next to an item, remove the rest)

• [x] Other, please explain:

What is the rationale for this request?

• Fix 'style regressions' from Adopt ES6 class syntax #979, and standardise some other ones
• Remove some leftover eslint-disable-xx's

What changes did you make? (Give an overview)

Example of style regression fixed

$('modal')	     
  .remove();	     
$('panel')	
  .remove();

// to
$('modal').remove();
$('panel').remove();

Is there anything you'd like reviewers to focus on?
na

Testing instructions:
na

Proposed commit message: (wrap lines at 72 characters)
Standardise code style and remove eslint disables

[openorclose]

I don't think we should need to go in and manually fix styling? If it's accepted by eslint, that should be good enough.

Too much time will be spent on commenting about code style in PRs otherwise.

That being said, it's good that some of the unnecessary eslint disables are removed.

[ang-zeyu]

I don't think we should need to go in and manually fix styling? If it's accepted by eslint, that should be good enough.

Too much time will be spent on commenting about code style in PRs otherwise.

That being said, it's good that some of the unnecessary eslint disables are removed.

Most of the style regressions were rather awkward, you could refer here #979 (review)
I think its always good to keep the code more readable especially for future developers

Too much time will be spent on commenting about code style in PRs otherwise.

Yes, this PR is specifically made for reverting the unintended code style changes though 😁

[yamgent]

Thanks, the cleanup looks pretty good 👍

[nbriannl]

Could you rebase your PR 🙂

[nbriannl]

👌