Adding eslint for our JSDocs

[Gabriel Luong]

Hi all,

I want to look into adding eslint rules to make sure we have consistent
JSDoc styling within DevTools as I am seeing a lot more inconsistent styles
within each different tool. I generally prefer the style that is found in
devtools/client/inspector/rules/rules.js which looks something like this:

/**
* Helper function for highlightRules that carries out highlighting the
given
* element if the search terms match the property, and returns a boolean
* indicating whether or not the search terms match.
*
* @param {DOMNode} element
* The node to highlight if search terms match
* @param {String} propertyName
* The property name of a rule
* @param {String} propertyValue
* The property value of a rule
* @return {Boolean} true if the given search terms match the property,
false
* otherwise.
*/

I have opened https://bugzilla.mozilla.org/show_bug.cgi?id=1319786 to
investigate this. If you have any preferences/feedback or are generally
interested, please add your notes there.

Thanks,
Gabriel