Pull args, intl, logging, shelf, and source_maps out of the SDK.

pkg/shelf/CHANGELOG.md

-## 0.5.6
-
-* Fixed `createMiddleware` to only catch errors if `errorHandler` is provided.
-
-* Updated `handleRequest` in `shelf_io` to more gracefully handle errors when
-  parsing `HttpRequest`.
-
-## 0.5.5+1
-
-* Updated `Request.change` to include the original `onHijack` callback if one
-  exists.
-
-## 0.5.5
-
-* Added default body text for `Response.forbidden` and `Response.notFound` if
-  null is provided.
-
-* Clarified documentation on a number of `Response` constructors.
-
-* Updated `README` links to point to latest docs on `www.dartdocs.org`.
-
-## 0.5.4+3
-
-* Widen the version constraint on the `collection` package.
-
-## 0.5.4+2
-
-* Updated headers map to use a more efficient case-insensitive backing store.
-
-## 0.5.4+1
-
-* Widen the version constraint for `stack_trace`.
-
-## 0.5.4
-
-* The `shelf_io` adapter now sends the `Date` HTTP header by default.
-
-* Fixed logic for setting Server header in `shelf_io`.
-
-## 0.5.3
-
-* Add new named parameters to `Request.change`: `scriptName` and `url`.
-
-## 0.5.2
-
-* Add a `Cascade` helper that runs handlers in sequence until one returns a
-  response that's neither a 404 nor a 405.
-
-* Add a `Request.change` method that copies a request with new header values.
-
-* Add a `Request.hijack` method that allows handlers to gain access to the
-  underlying HTTP socket.
-
-## 0.5.1+1
-
-* Capture all asynchronous errors thrown by handlers if they would otherwise be
-  top-leveled.
-
-* Add more detail to the README about handlers, middleware, and the rules for
-  implementing an adapter.
-
-## 0.5.1
-
-* Add a `context` map to `Request` and `Response` for passing data among
-  handlers and middleware.
-
-## 0.5.0+1
-
-* Allow `scheduled_test` development dependency up to v0.12.0
-
-## 0.5.0
-
-* Renamed `Stack` to `Pipeline`.
-
-## 0.4.0
-
-* Access to headers for `Request` and `Response` is now case-insensitive.
-
-* The constructor for `Request` has been simplified. 
-
-* `Request` now exposes `url` which replaces `pathInfo`, `queryString`, and 
-  `pathSegments`.
-
-## 0.3.0+9
-
-* Removed old testing infrastructure.
-
-* Updated documentation address.
-
-## 0.3.0+8
-
-* Added a dependency on the `http_parser` package.
-
-## 0.3.0+7
-
-* Removed unused dependency on the `mime` package.
-
-## 0.3.0+6
-
-* Added a dependency on the `string_scanner` package.
-
-## 0.3.0+5
-
-* Updated `pubspec` details for move to Dart SDK.
-
-## 0.3.0 2014-03-25
-
-* `Response`
-    * **NEW!** `int get contentLength`
-    * **NEW!** `DateTime get expires`
-    * **NEW!** `DateTime get lastModified`
-* `Request`
-    * **BREAKING** `contentLength` is now read from `headers`. The constructor
-      argument has been removed.
-    * **NEW!** supports an optional `Stream<List<int>> body` constructor argument.
-    * **NEW!** `Stream<List<int>> read()` and
-      `Future<String> readAsString([Encoding encoding])`
-    * **NEW!** `DateTime get ifModifiedSince`
-    * **NEW!** `String get mimeType`
-    * **NEW!** `Encoding get encoding`
-
-## 0.2.0 2014-03-06
-
-* **BREAKING** Removed `Shelf` prefix from all classes.
-* **BREAKING** `Response` has drastically different constructors.
-* *NEW!* `Response` now accepts a body of either `String` or
-  `Stream<List<int>>`.
-* *NEW!* `Response` now exposes `encoding` and `mimeType`.
-
-## 0.1.0 2014-03-02
-
-* First reviewed release