feat: export Pipeline for inheritances enabling (#675)

Export Pipeline for inheritances enabling

Author: eldadcohen1

lib/index.js

@@ -6,6 +6,7 @@ exports.ReplyError = require('redis-errors').ReplyError;
 exports.Cluster = require('./cluster');
 exports.Command = require('./command');
 exports.ScanStream = require('./ScanStream').default;
+exports.Pipeline = require('./pipeline');
 
 var PromiseContainer = require('./promiseContainer');
 Object.defineProperty(exports, 'Promise', {