Update install.sh

install.sh

@@ -36,8 +36,9 @@ echo ""
 echo "What mode of validation you want to use with  Acme.sh ?"
 echo "1) Cloudflare API validation (domain/subdomain/wildcard certs)"
 echo "2) Standalone mode validation (domain/subdomain certs)"
-echo ""
-read -r acmemode
+while [[ $acmemode != "1" && $acmemode != "2" ]]; do
+	read -r "Select an option [1-2]: " acmemode
+done
 echo ""
 
 # install ee-acme-cf or ee-acme-standalone