chore: refactor parts out of the index.js file

lib/utils.js

@@ -115,11 +115,26 @@ function replyInOrder (client, callback, err, res, queue) {
   }
 }
 
+/**
+ * @description Emit or print a warning. E.g. deprecations
+ *
+ * @param {RedisClient} client
+ * @param {string} msg
+ */
+function warn (client, msg) {
+  if (client.listeners('warning').length !== 0) {
+    client.emit('warning', msg)
+  } else {
+    console.warn('NodeRedis:', msg)
+  }
+}
+
 module.exports = {
   replyToStrings,
   replyToObject,
   errCode: /^([A-Z]+)\s+(.+)$/,
   monitorRegex: /^[0-9]{10,11}\.[0-9]+ \[[0-9]+ .+]( ".+?")+$/,
   clone: convenienceClone,
-  replyInOrder
+  replyInOrder,
+  warn
 }