Update Changelog, etc for 2.0.6

Author: Dan Richelson

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 All notable changes to the LaunchDarkly Java SDK will be documented in this file. This project adheres to [Semantic Versioning](http://semver.org).
 
+## [2.0.6] - 2017-02-07
+### Changed
+- Use minimum versions in composer.json
+
 ## [2.0.5] - 2017-02-03
 ### Changed
 - Made Monolog dependency version less strict

VERSION

@@ -1 +1 @@
-2.0.5
+2.0.6

src/LaunchDarkly/LDClient.php

@@ -10,7 +10,7 @@
  */
 class LDClient {
     const DEFAULT_BASE_URI = 'https://app.launchdarkly.com';
-    const VERSION = '2.0.5';
+    const VERSION = '2.0.6';
 
     /** @var string */
     protected $_sdkKey;