Update charted to 0.4.8 and roll

packages/quiver/lib/src/async/enumerate.dart

Index: packages/quiver/lib/src/async/enumerate.dart
diff --git a/packages/quiver/lib/src/streams/enumerate.dart b/packages/quiver/lib/src/async/enumerate.dart
similarity index 83%
rename from packages/quiver/lib/src/streams/enumerate.dart
rename to packages/quiver/lib/src/async/enumerate.dart
index 7978a05ec91f411dbf8a5fa044decdb8b1eba0dd..62148d7348dcb95349e879ccc6a93faa7d6ada27 100644
--- a/packages/quiver/lib/src/streams/enumerate.dart
+++ b/packages/quiver/lib/src/async/enumerate.dart
@@ -12,12 +12,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-part of quiver.streams;
+part of quiver.async;
 
-/**
- * Returns a [Stream] of [IndexedValue]s where the nth value holds the nth
- * element of [stream] and its index.
- */
+/// Returns a [Stream] of [IndexedValue]s where the nth value holds the nth
+/// element of [stream] and its index.
 Stream<IndexedValue> enumerate(Stream stream) {
   var index = 0;
   return stream.map((value) => new IndexedValue(index++, value));