Fix new_channel

Submitted by Matt Brubeck

THANKS

@@ -15,6 +15,7 @@ Antonio Cavedoni - Django templates
 Morten Frederiksen - expungeCache
 Lenny Domnitser - Coral CDN support for URLs with non-standard ports
 Amit Chakradeo  - Allow read-only files to be overwritten
+Matt Brubeck    - fix new_channel
 
 This codebase represents a radical refactoring of Planet 2.0, which lists
 the following contributors:

planet/shell/tmpl.py

@@ -102,7 +102,7 @@ Items = [
     ['enclosure_type', String, 'links', {'rel': 'enclosure'}, 'type'],
     ['id', String, 'id'],
     ['link', String, 'links', {'rel': 'alternate'}, 'href'],
-    ['new_channel', String, 'id'],
+    ['new_channel', String, 'source', 'id'],
     ['new_date', NewDate, 'published_parsed'],
     ['new_date', NewDate, 'updated_parsed'],
     ['rights', String, 'rights_detail', 'value'],

tests/data/filter/tmpl/new_channel.xml

@@ -0,0 +1,34 @@
+<!--
+Description:  source id
+Expect:       Items[0]['new_channel'] == 'http://example.com/' and not Items[1].has_key('new_channel') and Items[2]['new_channel'] == 'http://example.org/' and Items[3]['new_channel'] == 'http://example.com/'
+-->
+
+<feed xmlns="http://www.w3.org/2005/Atom">
+  <entry>
+    <source>
+      <id>http://example.com/</id>
+    </source>
+  </entry>
+  <entry>
+    <source>
+      <id>http://example.com/</id>
+    </source>
+  </entry>
+  <entry>
+    <source>
+      <id>http://example.org/</id>
+    </source>
+  </entry>
+  <entry>
+    <source>
+      <id>http://example.com/</id>
+    </source>
+  </entry>
+  <planet:source xmlns:planet='http://planet.intertwingly.net/'>
+    <id>http://example.com/</id>
+  </planet:source>
+  <planet:source xmlns:planet='http://planet.intertwingly.net/'>
+    <id>http://example.org/</id>
+  </planet:source>
+</feed>
+