added netcup dns api

README.md

@@ -320,6 +320,7 @@ You don't have to do anything manually!
 1. Loopia.se API
 1. acme-dns (https://github.com/joohoi/acme-dns)
 1. TELE3 (https://www.tele3.cz)
+1. netcup DNS API (https://www.netcup.de)
 
 And: