updated CHANGELOG with recent changes

Author: brosner

CHANGELOG

@@ -10,6 +10,11 @@ BI = backward incompatible change
    an optional sender
  * added received and sent methods taking a User instance to Notice.objects
  * New default behavior: single notice view now marks unseen notices as seen
+ * no longer optionally depend on mailer; use django.core.mail.send_mail and
+   we now encourge use of Django 1.2+ for mailer support
+ * notifications are not sent to inactive users
+ * users which do not exist when sending notification are now ignored
+ * BI: split settings part of notices view to its own view notice_settings
 
 0.1.5
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