Update libxmp, reorganize project structure, add Makefile

src/background.js

@@ -0,0 +1,28 @@
+browser.browserAction.onClicked.addListener(() => {
+	browser.tabs.create({
+		url: browser.runtime.getURL("player.html")
+	});
+});
+
+browser.webRequest.onBeforeRequest.addListener(
+	(details) => {
+		const url = details.url.toLowerCase();
+		if (isSupportedMediaUrl(url)) {
+			const playerUrl = browser.runtime.getURL("player.html") + "?media=" + encodeURIComponent(details.url);
+			
+			return { redirectUrl: playerUrl };
+		}
+
+		return {};
+	},
+	{
+		urls: ["<all_urls>"],
+		types: ["main_frame", "sub_frame"]
+	},
+	["blocking"]
+);
+
+function isSupportedMediaUrl(url) {
+	return url.match(/\.(669|amf|it|mod|mtm|mptm|s3m|stm|ult|uni|xm|umx)$/i) ||
+			url.match(/^(669|amf|it|mod|mtm|mptm|s3m|stm|ult|uni|xm|umx)\./i);
+}