Add gist comments docs

Author: cursedcoder

doc/README.md

@@ -6,6 +6,7 @@ APIs:
 * [Commits](commits.md)
 * [Enterprise](enterprise.md)
 * [Gists](gists.md)
+  * [Comments](gists/comments.md)
 * [Issues](issues.md)
   * [Comments](issue/comments.md)
   * [Labels](issue/labels.md)

doc/gists.md

@@ -1,7 +1,11 @@
 ## Gists API
 [Back to the navigation](README.md)
 
-Creating, editing, deleting and listing gists. Wraps [GitHub Gists API](http://developer.github.com/v3/gists/).
+Creating, editing, deleting and listing gists.
+Wraps [GitHub Gists API](http://developer.github.com/v3/gists/).
+
+Additional APIs:
+* [Comments](gists/comments.md)
 
 #### List all public gists.
 

doc/gists/comments.md

@@ -0,0 +1,51 @@
+## Gists / Comments API
+
+[Back to the "Gists API"](../gists.md) | [Back to the navigation](../README.md)
+
+Wraps [GitHub Issue Comments API](http://developer.github.com/v3/gists/comments/).
+
+### List a gist comments
+
+```php
+// for gist https://gist.github.com/danvbe/4476697
+$comments = $client->api('gist')->comments()->all('4476697');
+```
+
+* `4476697` : the id of the gist
+
+### Show a gist comment
+
+```php
+$comment = $client->api('gist')->comments()->show('4476697', '779656');
+```
+
+* `4476697` : the id of the gist
+* `779656` : the id of the comment
+
+### Create a gist comment
+
+```php
+$client->api('gist')->comments()->create('4476697', 'Hello World');
+```
+
+* `4476697` : the id of the gist
+* `Hello World` : the body of the comment
+
+### Update a gist comment
+
+```php
+$client->api('gist')->comments()->create('4476697', '123456', 'Hello Dolly');
+```
+
+* `4476697` : the id of the gist
+* `123456` : the id of the comment
+* `Hello Dolly` : the body of the updated comment
+
+### Remove a gist comment
+
+```php
+$client->api('gist')->comments()->remove('4476697', '123456');
+```
+
+* `4476697` : the id of the gist
+* `123456` : the id of the comment