[Projects] OSGeo Trac default notification setting updated

[Sandro Santilli]

We've changed default Trac activity notification preferences
so to NOT send email notification about a ticket change to
the author of the change.

Other listening parties (owner, assignee, those in Cc, etc.)
are still notified.

Any user can still opt-in to receive notifications by going to:

  https://trac.osgeo.org/${PROJECT}/prefs/notification
  (you need to be logged in)

Per-instance defaults can be tweaked but it needs to be done
by a SAC member (no web UI exists for that).

Please report to SAC (ticket to https://trac.osgeo.org/osgeo)
if you have any problem with this change or want to further
tweak your instance defaults.

--strk;
-