Provide information / link about the page version in the notification email, for a page update

In notification email the list of modified pages is sent to the user, with or without the actual difference, depending on the configuration in the user profile.

However, when the diff is included, there is no additional information in the email about the actual page version that triggered the notification. Thus, when the user will be reading the email (later), if the page has had other modifications in the meantime, there is no easy way to know what change the notification is referring. Ideally, a link to the version comparison that resulted in the change being notified (same as what is used to produce the diff in the email) would be sent, as it's the case for when the diff is not enabled.

This is specifically interesting for 2 things:

• being able to access the rendered diff (which is available from the wiki but not from the notif email),
• being able to evaluate quickly how (much) older the change is compared to the current version of the page - as this information would provide the version number for which the notification was sent.
• when the