Remove jQuery

[kx-chen]

Closes #1807

[ThiefMaster]

What's wrong with const? Unless we reassign I think const makes perfect sense.

[davidism]

I agree, use const if the value is not expected to change.

Do in general look for old patterns though, we probably shouldn't use var regardless.

[chrisnguyn]

Ready for maintainer review.

[obfusk]

tbtools.py still includes a <script> tag for jquery.js.

[ThiefMaster]

I would reformat it with prettier. Here's a decent config (but can be changed of course in case you prefer double quotes to be consistent with the Python style):

printWidth: 100
tabWidth: 2
useTabs: false
semi: true
singleQuote: true
quoteProps: 'consistent'
trailingComma: 'es5'
bracketSpacing: false
jsxBracketSameLine: false
arrowParens: 'avoid'
endOfLine: 'lf'

---

I'd also suggest running eslint with the recommended preset on the file and fix stuff it finds (many things may be autofixable).

[davidism]

Couldn't push to this branch, so squashed and rebased in #1857.