add alternativeto.net external link

README.md

@@ -420,6 +420,7 @@ CMS are a practical way to setup a website with many features. CMS often come wi
 ## External links
  * [Awesome Sysadmin](https://github.com/n1trux/awesome-sysadmin) -  A curated list of amazingly awesome open source sysadmin resources.
  * [PRISM Break](https://prism-break.org/en/), [Privacytools.io](https://www.privacytools.io/) - Mobile, computer & server privacy-minded applications
+ * [Self-hostable software on alternativeTo.net](https://alternativeto.net/?platform=self-hosted&sort=likes)
 
 
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