big ui update, page search + full text

- split file chooser from coll index, insert as header, make file chooser collapsible
- revamp collection index to be responsive
- add separate sorter component, used for collection index and pages
- combine 'curated lists' + pages, with page search + narrative
- ensure page + narrative lists are collapsible
- page search: support title, url and full text search if available, using flexsearch
- page search: keyword highlighting, load all pages, showing in increments of 100
- page and resource search: delay search to 1/4 sec of inactivity to avoid too many queries
- electron app: ensure noCache is set to true for local files
- embedding: remove separate embed.js, just use ui.js for embed as well
- embedding: support embedding iframe in a local origin with just sw.js and ui.js: sw.js serves index.html,
<replay-web-page> embed injects ui.js into iframe
- sw.js, new service worker entry point
- sw and ww inited only from <replay-app-main>, ui.js loaded from <replay-web-page> embed component

src/loader.js

@@ -1,12 +1,20 @@
 import { LitElement, html, css } from 'lit-element';
-import { wrapCss, dbworker } from './misc';
+import { wrapCss } from './misc';
 
 import { parseURLSchemeHostPath } from './pageutils';
 
+let dbworker = null;
+
 
 // ===========================================================================
 class Loader extends LitElement
 {
+  static initDBWorker() {
+    if (dbworker === null) {
+      dbworker = new Worker(__SW_NAME__);
+    }
+  }
+
   constructor() {
     super();
     this.progress = 0;
@@ -15,6 +23,8 @@ class Loader extends LitElement
     this.coll = "";
     this.state = "waiting";
     this.loadInfo = null;
+
+    Loader.initDBWorker();
   }
 
   static get properties() {
@@ -92,11 +102,7 @@ You can select a file to upload from the main page by clicking the \'Choose File
             return;
           }
 
-          source = {
-            sourceUrl: this.loadInfo.sourceUrl,
-            loadUrl: this.loadInfo.loadUrl,
-            name: this.loadInfo.name
-          }
+          source = this.loadInfo;
           break;
       }
     } catch (e) {}