Release 0.6.2

[westonruter]

• [x] Add contributor props.
• [x] Bump version numbers. ack -Q 0.6.1 $(git ls-files) and replace with 0.6.2 where appropriate
• [x] Make sure all unmilestoned PRs and issues are milestoned if fixed in release.
• [x] Add changelog to readme.
• [x] Draft new GitHub release tag 0.6.2 on master, with ZIP build via grunt build; cd build; zip -r ../customize-snapshots-0.6.2.zip *; cd -; cp customize-snapshots-0.6.2.zip ~/Downloads/customize-snapshots.zip, and with link to readme on tag tree: https://github.com/xwp/wp-customize-snapshots/blob/0.6.2/readme.md#changelog
• [x] Test build by installing plugin build ZIP.
• [x] Merge release PR.
• [x] Wait for Travis build for master branch to go ✅ .
• [x] Deploy to WordPress.org via grunt deploy. Remember to look at SVN diff.
• [x] Publish GitHub release.
• [x] Close GitHub milestone.

pbpaste | sed "s/$PREV_NEW/$NEXT_NEW/g" | sed "s/$PREV_OLD/$PREV_NEW/g" | sed 's:\[x:\[ :' | pbcopy