async flag for async eval ops

structure/client/components/commands/developer/Evaluate.js

@@ -1,5 +1,7 @@
 const { inspect } = require('util');
 const { username } = require('os').userInfo();
+
+const { Util } = require('../../../../../util');
 // eslint-disable-next-line no-unused-vars
 const moment = require('moment');
 
@@ -32,6 +34,12 @@ class Evaluate extends Command {
                     type: 'BOOLEAN',
                     types: ['FLAG'],
                     default: true
+                },
+                {
+                    name: 'async',
+                    type: 'BOOLEAN',
+                    types: ['FLAG'],
+                    default: true
                 }
             ],
             showUsage: true,
@@ -45,6 +53,7 @@ class Evaluate extends Command {
     async execute(message, { params, args }) {
 
         params = params.join(' ');
+        if (args.async) params = `(async () => {${params}})()`;
         const { guild, author, member, client } = message; //eslint-disable-line no-unused-vars
 
         try {