Release 0.8.5

[westonruter]

• [x] Add contributor props.
• [x] Bump version numbers. ack -Q 0.8.4 and replace with 0.8.5 where appropriate (this needs to be automated)
• [x] Add changelog to readme.
• [x] Draft new GitHub release tag 0.8.5 on master, with ZIP build via grunt build; cd build; zip -r ../customize-posts-0.8.5.zip *; cd -, and with link to readme on tag tree: https://github.com/xwp/wp-customize-posts/blob/0.8.5/readme.md#changelog
• [x] Test build.
• [x] Merge release PR.
• [x] Deploy to WordPress.org via grunt deploy. Remember to look at SVN diff.
• [x] Publish GitHub release.
• [x] Close GitHub milestone.