[telepathy-butterfly/master] MailNotification: Added more documentation

[Nicolas Dufresne]

Explained why we stub Subscribe/Unsubscribe method and added where
notifications come from.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne at collabora.co.uk>
---
 butterfly/mail_notification.py |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/butterfly/mail_notification.py b/butterfly/mail_notification.py
index 1bc668c..adaca13 100644
--- a/butterfly/mail_notification.py
+++ b/butterfly/mail_notification.py
@@ -79,6 +79,9 @@ class ButterflyMailNotification(
 
 
     def Subscribe(self):
+        # Papyon does not have enable/disable feature on mail tracking and
+        # does not use more memory while monitoring may. Thus we can safely
+        # stub subscribe/unsubscribe method.
         pass
 
 
@@ -115,6 +118,7 @@ class ButterflyMailNotification(
         return (id, HTTP_METHOD_POST, post_data)
 
 
+    # papyon.event.MailboxEventInterface
     def on_mailbox_new_mail_received(self, mail_message):
         logger.debug("New Mail " + str(mail_message))
 
@@ -132,6 +136,7 @@ class ButterflyMailNotification(
         self.MailsReceived([mail])
 
 
+    # papyon.event.MailboxEventInterface
     def on_mailbox_unread_mail_count_changed(self, unread_mail_count,
             initial=False):
         logger.debug("Unread Mail Count Changed " + str(unread_mail_count))
-- 
1.5.6.5