GitLab

I just saw a user build Tor from git, and he didn't have asciidoc installed, and ./configure gave him

      echo "==================================";
      echo;
      echo "You need asciidoc installed to be able to build the manpage.";
      echo "To build without manpages, use the --disable-asciidoc argument";
      echo "when calling configure.";
      echo;
      echo "==================================";
      exit 1;

which he interpreted as a successful run. We should make the above message more clear that it's a failure case.