httpserver: Adding nobots directive (#1767)

* Adding nobots directive

* Moving nobots directive behind log one.

* Move nobots directive to a better position

caddyhttp/httpserver/plugin.go

@@ -470,6 +470,7 @@ var directives = []string{
 	"redir",
 	"status",
 	"cors",   // github.com/captncraig/cors/caddy
+	"nobots", // github.com/Xumeiquer/nobots
 	"mime",
 	"login",     // github.com/tarent/loginsrv/caddy
 	"reauth",    // github.com/freman/caddy-reauth