Add support for dc:creator

[deadcoder0904]

Closes #130

[coveralls]

Coverage increased (+0.002%) to 99.573% when pulling 0118475 on deadcoder0904:master into 96c6aec on jpmonette:master.

[chazmcgarvey]

How about something like this?

• Adds the schema for dc, if creator is used.
• Allow multiple creators.
• Do author or creator, not both (as one best practice suggests).

[chazmcgarvey]

Suggested change

	entry.author.map((author: Author) => {
	item["dc:creator"] = { _cdata: author.name };
	if (author.email && author.name) {
	item.author.push({ _text: author.email + " (" + author.name + ")" });
	}
	item["dc:creator"] = [];
	entry.author.map((author: Author) => {
	if (author.email && author.name) {
	item.author.push({ _text: author.email + " (" + author.name + ")" });
	} else if (author.name) {
	isDublinCore = true;
	item["dc:creator"].push({ _cdata: author.name });
	}

And up above:

  let isDublinCore = false;

And down below:

  if (isDublinCore) {
    base.rss._attributes["xmlns:dc"] = "http://purl.org/dc/elements/1.1/";
  }

[paul-uz]

This should not be added to the RSS2 spec, as by definition, it is not in the RSS2 spec (https://validator.w3.org/feed/docs/rss2.html)

[chazmcgarvey]

This should not be added to the RSS2 spec, as by definition, it is not in the RSS2 spec (https://validator.w3.org/feed/docs/rss2.html)

Are you referring to the spec file modified by this pull request? That's a test file. "spec" in the filename does not mean it has anything to do with the RSS2 spec, it's just a Jest convention.

If you're saying this node module shouldn't use extra namespaces, consider this from the document you link:

RSS is by no means a perfect format, but it is very popular and widely supported. Having a settled spec is something RSS has needed for a long time. The purpose of this work is to help it become a unchanging thing, to foster growth in the market that is developing around it, and to clear the path for innovation in new syndication formats. Therefore, the RSS spec is, for all practical purposes, frozen at version 2.0.1. We anticipate possible 2.0.2 or 2.0.3 versions, etc. only for the purpose of clarifying the specification, not for adding new features to the format. Subsequent work should happen in modules, using namespaces, and in completely new syndication formats, with new names.

(Emphasis mine.)

Nobody is saying that the Dublin core namespace is part of the RSS2 spec. The RSS2 spec over time has proven to have problems and be incomplete, which is why new namespaces -- which have schemas apart from the RSS2 schema -- have added missing functionality. Dublin core is such a namespace. It is popular and well-supported by readers.