Allow extra files on 10.5

[juliushaertl]

Should make the web based migrator work together with an update of the update server hosted under https://updates.nextcloud.org/owncloud-migration/

• [x] Do not remove new apps-external directory that oC creates by default now
• [x] Fix too many requests response when downloading
• [x] Try to see if steps from https://nextcloud.com/migration/ still apply
• [ ] The update server would need to deliver 20.0.4 if the oC release is 10.5.x.x. @rullzer I could prepare a PR but I cannot find the code :wink:

Once merged

• [ ] Deploy to the download server at https://download.nextcloud.com/server/installer/migrator/index.php

Tested with the following additional patch:

diff --git a/index.php b/index.php
index d07d697..caf602a 100644
--- a/index.php
+++ b/index.php
@@ -409,6 +409,22 @@ class Updater {
         * @throws \Exception
         */
        private function getUpdateServerResponse() {
+               $response = [
+    'version' => '20.0.4.0',
+    'versionstring' => 'Nextcloud 20.0.4',
+       'url' => 'https://download.nextcloud.com/server/releases/nextcloud-20.0.4.zip',
+    'web' => 'https://docs.nextcloud.com/server/20/admin_manual/maintenance/upgrade.html',
+    'changes' => 'https://updates.nextcloud.com/changelog_server/?version=20.0.4',
+    'autoupdater' => 1,
+    'eol' => 0,
+    'signature' => 'NGnbpWWpZWcju26Av57gJd1cHusErTGHnt+r1cwPibd/MH6df9eb8xJhXcHeLSMt
+QI88IcZyX7Gavl5i5pB/zOANhOrgDTCaRokrfICFaL8ZhFHF1yK7oOTKhB3U3jQu
+sSdjxAg3azNcPXtAIJtEED38YnQFwHOIWeAaWAHvBzIxgG6fJh/iRsYM0+JsabBH
+LF55NkWIfsVvWS7ZpmAbIPWbh3t9DTdnQBdhXtIyyp+WxNtRuZP6bsIwoOs4HDgc
+oKV5Q9OpZ+a5p95jJUuEkOyqgzE7pyqQj/LZ990pBzKlgq3eKoIIFgZK3I/hOZXC
+zAQ3mXtrijNy/j9sloE03w=='
+       ];
+return $response;
                $this->silentLog('[info] getUpdateServerResponse()');

                $updaterServer = 'https://updates.nextcloud.org/owncloud-migration/';

[juliushaertl]

Pushed another fix for a strange invisible char that was somehow present before:

git diff --cached | cat -v
-       $shippedApps['shippedApps'][]M-BM- = 'example-theme';
+       $shippedApps['shippedApps'][] = 'example-theme';