Minor fixes for the workflow component

Author: javiereguiluz

components/workflow.rst

@@ -5,9 +5,12 @@
 The Workflow Component
 ======================
 
-    The Workflow component provides tools for managing a workflow or, finite state
+    The Workflow component provides tools for managing a workflow or finite state
     machine.
 
+.. versionadded:: 2.8
+    The Workflow component was introduced in Symfony 3.2.
+
 Installation
 ------------
 
@@ -17,3 +20,5 @@ You can install the component in 2 different ways:
 * Use the official Git repository (https://github.com/symfony/workflow).
 
 For more information, see the code in the Git Repository.
+
+.. _Packagist: https://packagist.org/packages/symfony/workflow