Prepare v0.1.0 release

Author: clue

CHANGELOG.md

@@ -0,0 +1,5 @@
+# Changelog
+
+## 0.1.0 (2016-04-12)
+
+* First tagged release

README.md

@@ -11,7 +11,7 @@ built on top of [React PHP](http://reactphp.org/).
 * [Install](#install)
 * [License](#license)
 
-> Note: This project is in early alpha stage! Feel free to report any issues you encounter.
+> Note: This project is in beta stage! Feel free to report any issues you encounter.
 
 ## Usage
 
@@ -98,9 +98,11 @@ The recommended way to install this library is [through Composer](https://getcom
 This will install the latest supported version:
 
 ```bash
-$ composer require clue/promise-stream:dev-master
+$ composer require clue/promise-stream:^0.1
 ```
 
+See also the [CHANGELOG](CHANGELOG.md) for details about version upgrades.
+
 ## License
 
 MIT