Add cname field (#3053)
Add cname field (#3053)

Summary:
So that the GItHub settings CNAME field is set upon publish.
Pull Request resolved: https://github.com/facebook/relay/pull/3053

Test Plan: Assuming JoelMarcey know what he's doing, then test in prod.

Reviewed By: jstejada

Differential Revision: D20776136

Pulled By: kassens

fbshipit-source-id: 02f14b5ab4850d08333a2be7b04b20f042c001eb

cpojer/relay,voideanvalue/relay,facebook/relay,kassens/relay,xuorig/relay,josephsavona/relay,facebook/relay,kassens/relay,atxwebs/relay,facebook/relay,xuorig/relay,kassens/relay,wincent/relay,kassens/relay,atxwebs/relay,kassens/relay,yungsters/relay,josephsavona/relay,atxwebs/relay,josephsavona/relay,facebook/relay,xuorig/relay,voideanvalue/relay,voideanvalue/relay,xuorig/relay,cpojer/relay,facebook/relay,wincent/relay,xuorig/relay,wincent/relay,voideanvalue/relay,wincent/relay,voideanvalue/relay,wincent/relay,wincent/relay,yungsters/relay,facebook/relay,yungsters/relay,atxwebs/relay,cpojer/relay,cpojer/relay,kassens/relay,voideanvalue/relay,xuorig/relay