Allow snippet section titles to be customized using document attributes

Closes gh-363

docs/src/docs/asciidoc/working-with-asciidoctor.adoc

@@ -45,6 +45,58 @@ operation::index[]
 
 
 
+[[working-with-asciidoctor-including-snippets-operation-titles]]
+===== Section titles
+
+For each snippet that's including using `operation` a section with a title will be
+created. Default titles are provided for the built-in snippets:
+
+|===
+| Snippet | Title
+
+| curl-request
+| Curl Request
+
+| http-request
+| HTTP request
+
+| http-response
+| HTTP response
+
+| httpie-request
+| HTTPie request
+
+| links
+| Links
+
+| request-body
+| Request body
+
+| request-fields
+| Request fields
+
+| response-body
+| Response body
+
+| response-fields
+| Response fields
+|===
+
+For snippets not listed in the table above, a default title will be generated by replacing
+`-` characters with spaces and capitalising the first letter. For example, the title for a
+snippet named `custom-snippet` will be "Custom snippet".
+
+The default titles can be customized using document attributes. The name of the attribute
+should be `operation-{snippet}-title`. For example, to customize the title of the
+`curl-request` snippet to be "Example request", use the following attribute:
+
+[source,indent=0]
+----
+:operation-curl-request-title: Example request
+----
+
+
+
 [[working-with-asciidoctor-including-snippets-individual]]
 ==== Including individual snippets