Updating polymer to use latest code_transformers

pkg/polymer/pubspec.yaml

 name: polymer
 version: 0.10.0-pre.4
 author: Polymer.dart Authors <web-ui-dev@dartlang.org>
 description: >
   Polymer.dart is a new type of library for the web, built on top of Web
   Components, and designed to leverage the evolving web platform on modern
   browsers.
 homepage: https://www.dartlang.org/polymer-dart/
 dependencies:
   analyzer: '>=0.13.0-dev.6 <0.14.0'
   args: '>=0.10.0 <0.11.0'
   barback: '>=0.9.0 <0.13.0'
   browser: '>=0.10.0 <0.11.0'
-  code_transformers: '>=0.0.1-dev.4 <0.1.0'
+  code_transformers: '>=0.1.0 <0.2.0'
   html5lib: '>=0.9.2 <0.10.0'
   logging: '>=0.9.0 <0.10.0'
   observe: '>=0.10.0-pre.0 <0.11.0'
   path: '>=0.9.0 <2.0.0'
   polymer_expressions: '>=0.10.0-pre.0 <0.11.0'
   smoke: '>=0.1.0-pre.1 <0.2.0'
   source_maps: '>=0.9.0 <0.10.0'
   template_binding: '>=0.10.0-pre.0 <0.11.0'
   web_components: '>=0.3.2 <0.4.0'
   yaml: '>=0.9.0 <0.10.0'
 dev_dependencies:
   unittest: '>=0.10.0 <0.11.0'
 transformers:
 # TODO(sigmund): uncomment when full codegen is ready.
 #- polymer/src/build/remove_mirrors
 #    $include: lib/polymer.dart
 - observe:
     files: lib/src/instance.dart
     # TODO(sigmund): uncomment once $include is available in the stable channel
     # (1.3.0) or when we really need a dependency on the latest dev channel.
     # $include: lib/src/instance.dart
 environment:
   sdk: '>=1.2.0 <2.0.0'