Add SharePoint element manifests for PortalSettings pages

- Created elements-v1.1.xml, elements-v2.xml, and elements.xml to define the PortalSettingsPage modules for different versions.
- Added upgrade actions for v1.1 and v2 to apply the respective element manifests.
- Ensured that the PortalSettings.aspx file is included in the SitePages library with appropriate settings.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "portal-settings",
-  "version": "0.0.1",
+  "version": "2.0.0",
   "private": true,
   "main": "lib/index.js",
   "engines": {
@@ -9,6 +9,7 @@
   "scripts": {
     "build": "gulp bundle",
     "clean": "gulp clean",
+    "package": "gulp clean && gulp bundle --ship && gulp package-solution --ship",
     "test": "gulp test"
   },
   "dependencies": {