Reason: Syntax proposal: Make `fun` unnecessary

[stroiman]

It would be awsome if you could write

xs |> List.map (x => x.y)

instead of

xs |> List.map (fun => x.y)

[chenglou]

Yes, that's part of the new syntax in master =)
Will close this once we release it

[chenglou]

Closing now because we're probably shipping soon!