Fixes Issue #471 with Publish

- Add sed to Dockerfile; this sed exists on publish script; breaks headings/nav in files without metadata
- Ensure sed runs over storage-driver/ subdir
- Add metadata to all the files (including specs) that don't have it; this ensures they display correctly on publish
- Implement the fix for the showing up in Github
- Update template with GITHUB IGNORES

Signed-off-by: Mary Anthony <mary@docker.com>

docs/spec/auth/token.md

@@ -1,3 +1,10 @@
+<!--GITHUB
+page_title: Docker Registry v2 Authentication
+page_description: Introduces the Docker Registry v2 authentication
+page_keywords: registry, images, repository, v2, authentication
+IGNORES-->
+
+
 # Docker Registry v2 authentication via central service
 
 Today a Docker Registry can run in standalone mode in which there are no