Merge pull request #37 from topcoder-platform/issue_dup

Adjust the Kakfa message form

Author: LieutenantRoger

src/services/ProcessorService.js

@@ -95,6 +95,7 @@ update.schema = {
     originator: Joi.string().required(),
     timestamp: Joi.date().required(),
     'mime-type': Joi.string().required(),
+    key: Joi.string().allow(null),
     payload: Joi.object().keys({
       id: Joi.string().uuid().required(),
       legacy: Joi.object().keys({