fix(docs): link to reference docs section on googleapis.dev (#128)

* fix(docs): reference docs should link to section of googleapis.dev with API reference

* fix(docs): make anchors work in jsdoc

Author: bcoe

.jsdoc.js

@@ -41,5 +41,8 @@ module.exports = {
     sourceFiles: false,
     systemName: '@google-cloud/promisify',
     theme: 'lumen'
+  },
+  markdown: {
+    idInHeadings: true
   }
 };

README.md

@@ -118,10 +118,12 @@ Apache Version 2.0
 
 See [LICENSE](https://github.com/googleapis/nodejs-promisify/blob/master/LICENSE)
 
-[client-docs]: https://googleapis.dev/nodejs/promisify/latest
+[client-docs]: https://googleapis.dev/nodejs/promisify/latest#reference
 
 [shell_img]: https://gstatic.com/cloudssh/images/open-btn.png
 [projects]: https://console.cloud.google.com/project
 [billing]: https://support.google.com/cloud/answer/6293499#enable-billing
 
-[auth]: https://cloud.google.com/docs/authentication/getting-started
+[auth]: https://cloud.google.com/docs/authentication/getting-started
+
+<a name="reference"></a>