Migrate to new cloud code interfaces

removes job status object, moves messasge method on req object

Adds 3.0.0 migration guide

Fixes nits about 3.0.0 documentation

Adds update guide to README

README.md

@@ -35,6 +35,7 @@ Parse Server works with the Express web application framework. It can be added t
 - [Ride the Bleeding Edge](#want-to-ride-the-bleeding-edge)
 - [Contributing](#contributing)
 - [Backers](#backers)
+- [Upgrading to 3.0.0](#upgrading-to-3.0.0)
 - [Sponsors](#sponsors)
 
 # Getting Started
@@ -380,6 +381,14 @@ Parse Server allows developers to choose from several options when hosting files
 
 `GridStoreAdapter` is used by default and requires no setup, but if you're interested in using S3 or Google Cloud Storage, additional configuration information is available in the [Parse Server guide](http://docs.parseplatform.org/parse-server/guide/#configuring-file-adapters).
 
+# Upgrading to 3.0.0
+
+Starting 3.0.0, parse-server uses the JS SDK version 2.0. 
+In short, parse SDK v2.0 removes the backbone style callbacks as well as the Parse.Promise object in favor of native promises.
+All the Cloud Code interfaces also have been updated to reflect those changes, and all backbone style response objects are removed and replaced by Promise style resolution.
+
+We have written up a [migration guide](3.0.0.md), hoping this will help you transition to the next major release.
+
 # Support
 
 For implementation related questions or technical support, please refer to the [Stack Overflow](http://stackoverflow.com/questions/tagged/parse.com) and [Server Fault](https://serverfault.com/tags/parse) communities.