Update CHANGELOG

pkgs/markdown/CHANGELOG.md

diff --git a/pkgs/markdown/CHANGELOG.md b/pkgs/markdown/CHANGELOG.md
index fffe73e..c7a373b 100644
--- a/pkgs/markdown/CHANGELOG.md
+++ b/pkgs/markdown/CHANGELOG.md
@@ -6,7 +6,10 @@
 * Improve autolink parsing.
 * Added new table syntax: `TableSyntax`.
 * Added new ExtensionSet that includes the table syntax: `ExtensionSet.gitHub`.
-* For development: added tool/travis.sh.
+* For development: added `tool/travis.sh`.
+* Support multiline Setext headers.
+* Handle loose-vs-strict list items better.
+* Support ordered lists that start with a number other than 1.
 
 ## 0.11.0+1
 

pkgs/markdown/README.md

diff --git a/pkgs/markdown/README.md b/pkgs/markdown/README.md
index be1e77e..fb0172d 100644
--- a/pkgs/markdown/README.md
+++ b/pkgs/markdown/README.md
@@ -69,6 +69,16 @@
   * `new InlineHtmlSyntax()`
   * `const FencedCodeBlockSyntax()`
 
+* `ExtensionSet.gitHub` includes five extensions:
+
+  * `new InlineHtmlSyntax()`
+  * `const FencedCodeBlockSyntax()`
+  * `const HeaderWithIdSyntax()`, which adds `id` attributes to ATX-style
+    headers, for easy intra-document linking.
+  * `const SetextHeaderWithIdSyntax()`, which adds `id` attributes to
+    Setext-style headers, for easy intra-document linking.
+  * `const TableSyntax()`
+
 ### Custom syntax extensions
 
 You can create and use your own syntaxes.