Move CurlClient to Pub so that it can access resources.

pkg/http/lib/http.dart

Index: pkg/http/lib/http.dart
diff --git a/pkg/http/lib/http.dart b/pkg/http/lib/http.dart
index 4ee2c612df53864c6c0260bc460b07d9ea09f6a3..d13b2fb6f10e5cfef79927411420234ddca17540 100644
--- a/pkg/http/lib/http.dart
+++ b/pkg/http/lib/http.dart
@@ -65,7 +65,6 @@ import 'src/response.dart';
 export 'src/base_client.dart';
 export 'src/base_request.dart';
 export 'src/base_response.dart';
-export 'src/curl_client.dart';
 export 'src/client.dart';
 export 'src/multipart_file.dart';
 export 'src/multipart_request.dart';