2.x update branch and year in contributing and readme md (ReactiveX#4135)

* 2.x update branch and year in contributing md

* Also (C) 2013-2016

Author: akarnokd

CONTRIBUTING.md

@@ -1,6 +1,6 @@
-# Contributing to RxJava
+# Contributing to RxJava 2.x
 
-If you would like to contribute code you can do so through GitHub by forking the repository and sending a pull request (on a branch other than `master`, `0.x`, `1.x`, or `gh-pages`).
+If you would like to contribute code you can do so through GitHub by forking the repository and sending a pull request targeting the branch `2.x`.
 
 When submitting code, please make every effort to follow existing conventions and style in order to keep the code as readable as possible.
 
@@ -14,7 +14,7 @@ If you are adding a new file it should have a header like this:
 
 ```
 /**
- * Copyright 2014 Netflix, Inc.
+ * Copyright 2016 Netflix, Inc.
  * 
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.

README.md

@@ -146,7 +146,7 @@ For bugs, questions and discussions please use the [Github Issues](https://githu
 
 ## LICENSE
 
-Copyright 2013 Netflix, Inc.
+Copyright 2013-2016 Netflix, Inc.
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.