Fix the issue with plugins not loaded in time (#162)

* Return promises to be resolved, not the plugin objects (with all other promises and metadata) itself

* Don't await `slideshowCreated`

It resolves _after_ this plugin should be loaded.

plugins/live-demo/plugin.js

@@ -123,18 +123,18 @@ document.addEventListener("slidechange", evt => {
 	}
 });
 
-await Inspire.slideshowCreated;
-
-if (Inspire.currentSlide?.classList.contains("demo")){
-	LiveDemo.init(Inspire.currentSlide);
-}
+Inspire.slideshowCreated.then(() => {
+	if (Inspire.currentSlide?.classList.contains("demo")){
+		LiveDemo.init(Inspire.currentSlide);
+	}
 
-// var io = new IntersectionObserver(entries => {
-// 	entries.forEach(entry => LiveDemo.init(entry.target));
-// });
+	// var io = new IntersectionObserver(entries => {
+	// 	entries.forEach(entry => LiveDemo.init(entry.target));
+	// });
 
-// $$(".demo.slide").forEach(demo => {
-// 	io.observe(demo);
-// });
+	// $$(".demo.slide").forEach(demo => {
+	// 	io.observe(demo);
+	// });
+});
 
 export {LiveDemo};

src/plugins.js

@@ -54,11 +54,8 @@ export function loadAll (plugins = registry) {
 		if (doLoad && !dontLoad) {
 			let plugin = load(id, def);
 			// plugin.loaded.then(_ => ret.push(plugin));
-			plugin.loaded.then(
-				plugin => ret.push(plugin),
-
-			).catch(e => console.error(`Plugin ${id} error:`, e))
-			;
+			plugin.loaded.catch(e => console.error(`Plugin ${id} error:`, e));
+			ret.push(plugin.loaded);
 		}
 	}