Support Svelte 3

fixes #546, #551, #552, #554

test/apps/css/src/client.js

@@ -1,4 +1,4 @@
-import * as sapper from '../__sapper__/client.js';
+import * as sapper from '@sapper/app';
 
 window.start = () => sapper.start({
 	target: document.querySelector('#sapper')

test/apps/css/src/routes/bar.html

@@ -1,11 +1,13 @@
-<svelte:component this={Title}/>
-
 <script>
-	export default {
-		oncreate() {
-			import('./_components/Title.html').then(({ default: Title }) => {
-				this.set({ Title });
-			});
-		}
-	};
-</script>
+	import { onMount } from 'svelte';
+
+	export let Title;
+
+	onMount(() => {
+		import('./_components/Title.html').then(mod => {
+			Title = mod.default;
+		});
+	});
+</script>
+
+<svelte:component this={Title}/>

test/apps/css/src/server.js

@@ -1,5 +1,5 @@
 import polka from 'polka';
-import * as sapper from '../__sapper__/server.js';
+import * as sapper from '@sapper/server';
 
 const { PORT } = process.env;
 

test/apps/css/src/service-worker.js

@@ -1,10 +1,10 @@
-import { timestamp, files, shell, routes } from '../__sapper__/service-worker.js';
+import * as sapper from '@sapper/service-worker';
 
-const ASSETS = `cache${timestamp}`;
+const ASSETS = `cache${sapper.timestamp}`;
 
 // `shell` is an array of all the files generated by webpack,
 // `files` is an array of everything in the `static` directory
-const to_cache = shell.concat(ASSETS);
+const to_cache = sapper.shell.concat(sapper.files);
 const cached = new Set(to_cache);
 
 self.addEventListener('install', event => {
@@ -65,7 +65,7 @@ self.addEventListener('fetch', event => {
 	// might prefer a cache-first approach to a network-first one.)
 	event.respondWith(
 		caches
-			.open(`offline${timestamp}`)
+			.open(`offline${sapper.timestamp}`)
 			.then(async cache => {
 				try {
 					const response = await fetch(event.request);