Should options be a non-optional parameter #98
Description
In this PR, we make it optional: https://github.com/apple/swift-http-api-proposal/pull/97/changes
But we also discussed making it non-optional in the requested perform method on the protocol, and then adding default implementation to the protocol extension that just excludes the options parameter, and provides the result of self.makeDefaultOptions().
I think that's a nicer spelling as it allows adopters to rely on the fact that omitting the parameter will always match the behavior to explicitly calling client.makeDefaultOptions(). Plus it avoids potential confusion about "what does nil represent here" (which has historically been non-trivial for things like completion queues, etc).