Connector implementation crates have to pick http1/http2 #2376
Description
The low-level connection APIs like Connected/Connection/HttpConnector all require one of http1 or http2 to be set. This means that external crates like hyper-openssl have to pick one of those features to enable, which is kind of out of scope for what they actually need to do. It would probably make sense for those bits of the client API to only require client and not http1 or http2 to make things less weird.