Intention is to partition the demo into multiple files, so that the
main program is quite easy to follow.
1. connectlib.c: For any URL parsing and TCP connection related stuff
2. sh2lib.c: Convenience functions for HTTP2+TLS. The goal here is to
expose a simpler API than nghttp2. If most usecases end up being
served with this library, it could potentially be moved into a separate
component
