* Move next to download button and match styling

Co-authored-by: Aldrin Abastillas <AAbastillas@rcanalytics.com>
Co-authored-by: Tim Lai <timothy.lai@gmail.com>

* move Mocha-run tests to `test/mocha`

* fix relative paths

* fix JSX test paths

* update stagnated JSX tests

* `test/setup.js` -> `test/mocha/setup.js`

* use regex+globstar for test matching

* remove `console.log`

* housekeeping: `.js` -> `.jsx` where necessary

* Wrong usage of https://lodash.com/docs/4.17.5#lowerCase

* Add basic tests about ResponseBody Content-Type