Add tags support to evernote plugin

Relates to Issue #2268

I tried to map over the list of tags but NodeLists are not arrays and so
need to be converted. This looks ugly and probably should be abstracted
to a function. Come to think of it should we have a `$tw.utils.map()`
function?

plugins/tiddlywiki/evernote/modules/enex-deserializer.js

@@ -37,6 +37,7 @@ exports["application/enex+xml"] = function(text,fields) {
 		var result = {
 			title: noteNode.querySelector("title").textContent,
 			type: "text/html",
+			tags: Array.prototype.slice.call(noteNode.querySelectorAll("tag")).map(function(tag) { return tag.textContent; }).join(","),
 			text: noteNode.querySelector("content").textContent
 		};
 		$tw.utils.each(noteNodes.querySelector("note-attributes").childNodes,function(attrNode) {