* 'master' of github.com:gatsbyjs/gatsby: (63 commits)
  Update how-to-contribute.md to mention the style guide when writing blogs/tutorials (gatsbyjs#9742)
  Added  Tylermcginnis website (gatsbyjs#9619)
  Fix grammar and punctuation (gatsbyjs#9498)
  Fix typo of plugin authoring (gatsbyjs#9737)
  Authentication tutorial - small fixes (gatsbyjs#9738)
  chore: move run-sift (gatsbyjs#9549)
  docs: fix minor typo (gatsbyjs#9730)
  chore(release): Publish
  fix(gatsby-plugin-page-creator): ensure that __tests__ directory is actually ignored (gatsbyjs#9720)
  fix: revert admin redirect (gatsbyjs#9728)
  fix: adjust page order to make nested matchPaths work (gatsbyjs#9719)
  feat(gatsby-plugin-sharp): cache base64 if possible (gatsbyjs#9059)
  chore(release): Publish
  fix(gatsby-plugin-offline): Serve the offline shell for short URLs + use no-cors for external resources (gatsbyjs#9679)
  chore(release): Publish
  fix: ensure babel-preset-gatsby can be used with unit tests (gatsbyjs#9629)
  feat(www): Filter posts by date (gatsbyjs#9400)
  fix(blog): azure blog post url date (gatsbyjs#9718)
  feat(blog): Add post on publishing to Azure (gatsbyjs#8868)
  Emphasize importance of promise return on source-plugin docs (gatsbyjs#9650)
  ...

- Changed gatsbyjs.org links from absolute to relative
- Fixed passportjs link
- Changed sidebar link to show as available content (dark)