Update CHANGELOG.md

##[3.0.0-beta9] - 2020-05-29
###Fix
- Remove empty Expect HTTP header in Client
- Fix "400 Bad request" on Document.create #22 (Thanks @fdglefevre)

CHANGELOG.md

@@ -1,5 +1,18 @@
 #Teknoo Software - Sellsy client library - Change Log
 
+##[3.0.0-beta9] - 2020-05-29
+###Fix
+- Remove empty Expect HTTP header in Client
+- Fix "400 Bad request" on Document.create #22 (Thanks @fdglefevre)
+
+##[3.0.0-beta8] - 2020-03-12
+###Change
+- Switch Guzzle6 and HttpPlug implementations from main namespace to dedicated infrastructures namespace :
+    * `Teknoo\Sellsy\Transport\Guzzle6` become `Teknoo\Sellsy\Guzzle6\Transport\Guzzle6`
+    * `Teknoo\Sellsy\Transport\Guzzle6Promise` become `Teknoo\Sellsy\Guzzle6\Transport\Guzzle6Promise`
+    * `Teknoo\Sellsy\Transport\HttpPlug` become `Teknoo\Sellsy\Guzzle6\Transport\HttpPlug`
+    * `Teknoo\Sellsy\Transport\HttpPlugPromise` become `Teknoo\Sellsy\Guzzle6\Transport\HttpPlugPromise`
+
 ##[3.0.0-beta8] - 2020-03-12
 ###Change
 - Switch Guzzle6 and HttpPlug implementations from main namespace to dedicated infrastructures namespace :