PR proposal: Add JSDoc types

[barakplasma]

Would you accept a PR which added JSDoc types?

For example:

/**
 * @typedef {number | [number, number]} locationCoordinate
 */
/**
 * @param {locationCoordinate} lat
 * @param {locationCoordinate} lon
 */
HebcalProto.setLocation = function(lat, lon) {
    this.months.forEach(function(m){
        m.setLocation(lat, lon);
    });
    return this;
};

This could assist users of VS Code with Intellisense via JSDoc. Additionally, lets us run a bit of Typescript checking on the library. See also https://www.typescriptlang.org/docs/handbook/type-checking-javascript-files.html#supported-jsdoc

[Scimonster]

That would be awesome!

[Arrow7000]

@barakplasma I'd be really grateful if you did this!