fix(legacy): support legacy import expectations

Author: mbroadst

index.js

@@ -1,9 +1,15 @@
 'use strict';
 
+const kerberos = require('./lib/kerberos');
+
 // Get the Kerberos library
-module.exports = require('./lib/kerberos');
+module.exports = kerberos; 
+
+// Support for legacy versions of the mongodb driver expect this export
+module.exports.Kerberos = kerberos; 
 
 // Set up the auth processes
 module.exports.processes = {
   MongoAuthProcess: require('./lib/auth_processes/mongodb').MongoAuthProcess
 };
+