Make isUtc a getter, change some method names in Date.

samples/swarm/DataSource.dart

Index: samples/swarm/DataSource.dart
diff --git a/samples/swarm/DataSource.dart b/samples/swarm/DataSource.dart
index efb3f605a4e5cdbb450a685a6fa3bab3a7757ec7..042da41a7c0af69f2f8d348109cabb65255e23da 100644
--- a/samples/swarm/DataSource.dart
+++ b/samples/swarm/DataSource.dart
@@ -240,7 +240,8 @@ class Article {
     final author = decoder.readString();
     final dateInSeconds = decoder.readInt();
     final snippet = decoder.readString();
-    final date = new Date.fromEpoch(dateInSeconds*1000, isUtc: true);
+    final date =
+        new Date.fromMillisecondsSinceEpoch(dateInSeconds*1000, isUtc: true);
     return new Article(source, id, date, title, author, srcUrl, hasThumbnail,
         snippet);
   }