Split Mac and iOS specific javascript into individual files.

Mac/MainWindow/Detail/main_mac.js

@@ -0,0 +1,19 @@
+// These mouse functions are used by NetNewsWire for Mac to display link previews
+function mouseDidEnterLink(anchor) {
+	window.webkit.messageHandlers.mouseDidEnter.postMessage(anchor.href);
+}
+function mouseDidExitLink(anchor) {
+	window.webkit.messageHandlers.mouseDidExit.postMessage(anchor.href);
+}
+
+// Add the mouse listeners for the above functions
+function linkHover() {
+	document.querySelectorAll("a").forEach(element => {
+		element.addEventListener("mouseenter", function() { mouseDidEnterLink(this) });
+		element.addEventListener("mouseleave", function() { mouseDidExitLink(this) });
+	});
+}
+
+function postRenderProcessing() {
+	linkHover()
+}