docs: Add Code Review to Contributing.md (#402)

Author: derekneuland

CONTRIBUTING.md

@@ -16,6 +16,7 @@ Hello! Thank you for choosing to help contribute to one of the Twilio SendGrid o
 - [Testing](#testing)
 - [Style Guidelines & Naming Conventions](#style-guidelines--naming-conventions)
 - [Creating a Pull Request](#creating-a-pull-request)
+- [Code Reviews](#code-reviews)
 
 <a name="roadmap"></a>
 We use [Milestones](https://github.com/sendgrid/sendgrid-java/milestones) to help define current roadmaps, please feel free to grab an issue from the current milestone. Please indicate that you have begun work on it to avoid collisions. Once a PR is made, community review, comments, suggestions and additional PRs are welcomed and encouraged.
@@ -211,6 +212,9 @@ Please run your code through:
    ```
 
 7. [Open a Pull Request](https://help.github.com/articles/using-pull-requests/)
-    with a clear title and description against the `development` branch. All tests must be passing before we will review the PR.
+    with a clear title and description against the `master` branch. All tests must be passing before we will review the PR.
+    
+## Code Reviews<a name="code-reviews"></a>
+If you can, please look at open PRs and review them. Give feedback and help us merge these PRs much faster! If you don't know how, Github has some <a href="https://help.github.com/articles/about-pull-request-reviews/">great information on how to review a Pull Request.</a>
 
 If you have any additional questions, please feel free to [email](mailto:dx@sendgrid.com) us or create an issue in this repo.