Summary:
Pull Request resolved: https://github.com/facebook/yoga/pull/1587
Adds release notes for Yoga 3.0. Tentatively going to try to polish up the rest of the website bits, to be able to put this out on Monday.
If we get the website bits finished, I will add some bits about the new documentation.
Reviewed By: joevilches
Differential Revision: D54560841
fbshipit-source-id: 237f94985d2b804cf5a1e1737a23dc8a7a03695a
