Stream#underlying should return A instead of Unit?

[xuwei-k]

procedure syntax 😢

We should fix

- def underlying[A]
+ def underlying[A]: Unit

or

- def underlying[A]
+ def underlying[A]: A

? 🤔

• https://github.com/eed3si9n/gigahorse/blob/f595d6d5aea708ee1e08f92500311d002676b4fc/core/src/main/scala/gigahorse/Stream.scala#L22-L26
• https://github.com/eed3si9n/gigahorse/blob/f595d6d5aea708ee1e08f92500311d002676b4fc/asynchttpclient/src/main/scala/gigahorse/support/asynchttpclient/AhcStream.scala#L24-L28
• https://github.com/eed3si9n/gigahorse/blob/f595d6d5aea708ee1e08f92500311d002676b4fc/akka-http/src/main/scala/gigahorse/support/akkahttp/AkkaHttpStream.scala#L26-L30

[eed3si9n]

It should be def underlying[A]: A.