Add docs link to README.md

Author: KartoffelChipss

README.md

@@ -4,6 +4,7 @@
 ![purpur](https://cdn.jsdelivr.net/npm/@intergrav/devins-badges@3/assets/compact/supported/purpur_vector.svg)
 [![github](https://cdn.jsdelivr.net/npm/@intergrav/devins-badges@3/assets/compact/available/github_vector.svg)](https://github.com/KartoffelChipss/ServerLinksZ)
 [![modrinth](https://cdn.jsdelivr.net/npm/@intergrav/devins-badges@3/assets/compact/available/modrinth_vector.svg)](https://modrinth.com/plugin/serverlinksz)
+[![docs](https://cdn.jsdelivr.net/npm/@intergrav/devins-badges@3/assets/compact/documentation/gitbook_vector.svg)](https://docs.zetaplugins.com/serverlinksz)
 [![discord-plural](https://cdn.jsdelivr.net/npm/@intergrav/devins-badges@3/assets/compact/social/discord-plural_vector.svg)](https://strassburger.org/discord)
 [![generic-plural](https://cdn.jsdelivr.net/npm/@intergrav/devins-badges@3/assets/compact/translate/generic-plural_vector.svg)](https://gitlocalize.com/repo/9890)