[NEW FEATURE RELEASED]: Added support for HTTP/2 over TLS

[azagniotov]

As of v7.4.0 of stubby4j, as a new feature support for HTTP/2 over TLS using ALPN extension is available. See Support for HTTP/2 on HTTPS URIs over TLS section

Also, completely revisited TLS configuration in stubby4j, which enables support for TLSv1.0, TLSv1.1, TLSv1.2 and TLSv1.3. See Making requests over TLS section