Optionally ignore some notice sources for public page

We optionally ignore some notice sources from the public page.
Typically these are automatic notice sources like twitterfeed that
don't usually represent the community on the site very well.

classes/Notice.php

@@ -136,10 +136,12 @@ class Notice extends Memcached_DataObject
         $notice->profile_id = $profile_id;
 
         $blacklist = common_config('public', 'blacklist');
+        $autosource = common_config('public', 'autosource');
 
         # Blacklisted are non-false, but not 1, either
 
-        if ($blacklist && in_array($profile_id, $blacklist)) {
+        if (($blacklist && in_array($profile_id, $blacklist)) ||
+            ($source && $autosource && in_array($source, $autosource))) {
             $notice->is_local = -1;
         } else {
             $notice->is_local = $is_local;

config.php.sample

@@ -107,6 +107,14 @@ $config['sphinx']['port'] = 3312;
 #$config['public']['blacklist'][] = 123;
 #$config['public']['blacklist'][] = 2307;
 
+#Mark certain notice sources as automatic and thus not
+#appropriate for public feed
+#$config['public]['autosource'][] = 'twitterfeed';
+#$config['public]['autosource'][] = 'rssdent';
+#$config['public]['autosource'][] = 'Ping.Fm';
+#$config['public]['autosource'][] = 'HelloTxt';
+#$config['public]['autosource'][] = 'Updating.Me';
+
 #Do notice broadcasts offline
 #If you use this, you must run the six offline daemons in the
 #background. See the README for details.

lib/common.php

@@ -100,7 +100,8 @@ $config =
         array('server' => null),
         'public' =>
         array('localonly' => true,
-              'blacklist' => array()),
+              'blacklist' => array(),
+              'autosource' => array()),
         'theme' =>
         array('server' => null),
         'throttle' =>