Fix release date

CHANGELOG.md

@@ -1,4 +1,4 @@
-* 1.0.0-alpha6 (2012-10-22)
+* 1.0.0-alpha6 (2012-10-23)
 
   * Schema: Added ability to pass additional options to repositories (i.e. ssh keys/client certificates to secure private repos)
   * Schema: Added a new `~` operator that should be prefered over `>=`, see http://getcomposer.org/doc/01-basic-usage.md#package-versions