SIGHUP is sent when the tty is detached and by default kills the process. When we run in the background we don't care anymore about the tty, so it should be safe for us to ignore SIGHUP. (frankly, I expected daemon(3) to do stuff like this for us).

With new IRI, parser the old assumption of path starting with ./ is no longer valid.

This extends the URI parser so it supports full IRI (Internationalized Resource Identifiers, RFC3987). Some areas of it can/may be improved, but here's a start. Note: we assume UTF-8 encoded IRI.

Up until now I used a "poor man" approach: the uri parser is barely a parser, it tries to extract the path from the request, with some minor checking, and that's all. This obviously is not RFC3986-compliant. The new RFC3986 (URI) parser should be fully compliant. It may accept some invalid URI, but shouldn't reject or mis-parse valid URI. (in particular, the rule for the path is way more relaxed in this parser than it is in the RFC text). A difference with RFC3986 is that we don't even try to parse the (optional) userinfo part of a URI: following the Gemini spec we treat it as an error. A further caveats is that %2F in the path part of the URI is indistinguishable from a literal '/': this is NOT conforming, but due to the scope and use of gmid, I don't see how treat a %2F sequence in the path (reject the URI?).