Restrict new windows in replay + improved service worker loading + better error messages (#126)

* embeds:
- support target rewriting with named iframe as per webrecorder/wombat#94
- refactor sw init: detect additional errors, such as CORS issues in nested iframes
- support cross-origin replaybase for embeds
- add 'requirecrossoriginiframe' to restrict embed to only be loaded in subdomain iframes, otherwise showing
- rename noSandbox -> sandbox, not enabled by default

init: set appName on service worker init
docs:
- add example embed to embedding doc
- update docs for noSandbox -> sandbox
- add warning if deprecated 'noSandbox' flag is used, explaining that it is now deprecated
- update embedding and CHANGES.md with latest features
- add tweet-example.wacz
- add embed.html to test embeds

bump to 1.7.0-beta.1

_data/package.json

@@ -1,7 +1,7 @@
 {
   "name": "replaywebpage",
   "productName": "ReplayWeb.page",
-  "version": "1.7.0-beta.0",
+  "version": "1.7.0-beta.1",
   "description": "Serverless Web Archive Replay",
   "repository": "https://github.com/webrecorder/replayweb.page",
   "homepage": "https://replayweb.page/",
@@ -9,7 +9,7 @@
   "license": "AGPL-3.0-or-later",
   "dependencies": {
     "@fortawesome/fontawesome-free": "^5.15.4",
-    "@webrecorder/wabac": "^2.13.0-beta.0",
+    "@webrecorder/wabac": "github:webrecorder/wabac.js",
     "bulma": "^0.9.3",
     "electron-log": "^4.4.1",
     "electron-updater": "^4.3.9",