style(dart/transform): Remove src from library directives

Conform to Angular 2 style by removing `src` from library directives.
Completed with:
```
find -name "*.dart" | xargs sed -i -e 's!library\(.*\)src\.\(.*\)!library \1\2!'
```

Closes #1005

Closes #1038

modules/angular2/src/transform/in_progress/resolvers.dart

@@ -1,4 +1,4 @@
-library angular2.src.transform;
+library angular2.transform;
 
 import 'package:barback/barback.dart';
 import 'package:analyzer/src/generated/element.dart';