Constant solicit::http::ALPN_PROTOCOLS

pub const ALPN_PROTOCOLS: &'static [&'static [u8]] = &[b"h2", b"h2-16", b"h2-15", b"h2-14"]

A set of protocol names that the library should use to indicate that HTTP/2 is supported during protocol negotiation (NPN or ALPN). We include some of the drafts' protocol names, since there is basically no difference for all intents and purposes (and some servers out there still only officially advertise draft support). TODO: Eventually only use "h2".