Summary:
Yesterday we shipped hermesengine.dev as part of the current 0.60 release. This PR brings those changes to master.
## Changelog
[General] [Added] - Added support for Hermes
Pull Request resolved: https://github.com/facebook/react-native/pull/25613
Test Plan:
* CI is green both on GitHub and at FB
* Creating a new app from source can use Hermes on Android
Reviewed By: cpojer
Differential Revision: D16221777
Pulled By: willholen
fbshipit-source-id: aa6be10537863039cb666292465ba2e1d44b64ef
d7f5153cd8