updated ordering of changelog items

CHANGELOG.md

 ## 1.15.0
 
 ### Language features
 * Added support for [configuration-specific imports](https://github.com/munificent/dep-interface-libraries/blob/master/Proposal.md).
   On the VM and dart2js, they can be enabled with `--conditional-directives`.
 
   The analyzer requires an additional option in an `options` file:
-  ```
+  ```yaml
   analyzer:
     language:
       enableConditionalDirectives: true
   ```
   Then run the analyzer with `--options=<path-to-options-file>`.
 
 ### Core library changes
-* Added `Uri.queryParametersAll` to handle multiple query parameters with
-  the same name.
+
+* `dart:async`
+  * Made `StreamView` class a `const` class.
+
+* `dart:core`
+  * Added `Uri.queryParametersAll` to handle multiple query parameters with
+    the same name.
 
 * `dart:io`
   * Added `SecurityContext.usePrivateKeyBytes`,
-          `SecurityContext.useCertificateChainBytes`,
-          `SecurityContext.setTrustedCertificatesBytes`, and
-          `SecurityContext.setClientAuthoritiesBytes`.
+    `SecurityContext.useCertificateChainBytes`,
+    `SecurityContext.setTrustedCertificatesBytes`, and
+    `SecurityContext.setClientAuthoritiesBytes`.
   * The non-`Bytes` methods of `SecurityContext` are being renamed -`Sync`, as
     they will do synchronous IO. The non-`Bytes` and non-`Sync` methods are
     deprecated and will be removed in a later release.
   * **Breaking** The named `directory` argument of
     `SecurityContext.setTrustedCertificates` is no longer supported.
     The method now only supports one argument for the PEM file name containing
     the trusted certificates.
-  * Added support to SecurityContext for PKCS12 certificate and key containers.
+  * Added support to `SecurityContext` for PKCS12 certificate and key
+    containers.
   * All calls in `SecurityContext` that accept certificate data now accept an
     optional named parameter `password`, similar to
     `SecurityContext.usePrivateKeyBytes`, for use as the password for PKCS12
     data.
-* `dart:async`
-  * Made `StreamView` class a `const` class.
 
 ## 1.14.2 - 2016-02-09
 
 * Fixes a bug where pub would download packages from pub.dartlang.org even when
   a different hosted URL was specified.
 
 ## 1.14.1 - 2016-02-04
 
 Patch release, resolves one issue:
 
@@ skipping 757 matching lines @@
     they will keep the Dart process alive until they time out. This fixes the
     handling of persistent connections. Previously, the client would shut down
     immediately after a request.
 
   * **Breaking change:** `HttpServer` no longer compresses all traffic by
     default. The new `autoCompress` property can be set to `true` to re-enable
     compression.
 
 * `dart:isolate`: `Isolate.spawnUri` added the optional `packageRoot` argument,
   which controls how it resolves `package:` URIs.