Roll Observatory packages and add a roll script

packages/initialize/tool/rename_build_outputs.dart

+library initialize.tool.rename_build_outputs;
+
+import 'dart:io';
+
+import 'package:path/path.dart';
+
+main() {
+  var scriptPath = Platform.script.path;
+  if (context.style.name == 'windows') scriptPath = scriptPath.substring(1);
+  var dir = join(dirname(dirname(scriptPath)), 'build', 'test');
+  for (var file in new Directory(dir).listSync()) {
+    var filepath = file.path;
+    var name = basename(filepath);
+    if (name.endsWith('.initialize.dart')) {
+      var newPath = join(dirname(filepath),
+          name.replaceFirst('.initialize.dart', '.initialize_test.dart'));
+      print('Copying $filepath to $newPath');
+      new File(filepath).copySync(newPath);
+    }
+  }
+}