update Seafile demo URL

README.md

@@ -704,7 +704,7 @@ See https://github.com/n1trux/awesome-sysadmin#distributed-filesystems
 - [ownCloud](https://owncloud.org/) - All-in-one solution for saving, synchronizing, viewing, editing and sharing files, calendars, address books and more. ([Source Code](https://github.com/owncloud/core), [Clients](https://github.com/owncloud/core/wiki/Apps)) `AGPL-3.0` `PHP`
 - [Pydio](https://pydio.com/) - Turn any web server into a powerful file management system and an alternative to mainstream cloud storage providers. ([Source Code](https://github.com/pydio/pydio-core)) `AGPL-3.0` `PHP`
 - [Samba](https://www.samba.org/) - Samba is the standard Windows interoperability suite of programs for Linux and Unix. It provides secure, stable and fast file and print services for all clients using the SMB/CIFS protocol. ([Source Code](https://git.samba.org/samba.git/)) `GPL-3.0` `C`
-- [Seafile](https://www.seafile.com/en/home/) - File hosting and sharing solution primary for teams and organizations. ([Demo](https://seacloud.cc/demo), [Source Code](https://github.com/haiwen/seafile)) `GPL-2.0` `C`
+- [Seafile](https://www.seafile.com/en/home/) - File hosting and sharing solution primary for teams and organizations. ([Demo](https://demo.seafile.com/demo), [Source Code](https://github.com/haiwen/seafile)) `GPL-2.0` `C`
 - [SparkleShare](http://sparkleshare.org/) - Self hosted, instant, secure file sync. ([Source Code](https://github.com/hbons/SparkleShare)) `GPL-3.0` `C#`
 - [Syncany](https://www.syncany.org/) - Secure file sync software for arbitrary storage backends, an open-source cloud storage and filesharing application. Securely synchronize your files to any kind of storage. `GPL-3.0` `Java`
 - [Syncthing](https://syncthing.net/) - Syncthing is an open source peer-to-peer file synchronisation tool. ([Source Code](https://github.com/syncthing/syncthing)) `MPL-2.0` `Go`