redstore: add home page and license fields

pkgs/servers/http/redstore/default.nix

···
 
   meta = {
     description = "An HTTP interface to Redland RDF store";
+    homepage = https://www.aelius.com/njh/redstore/;
     maintainers = [ stdenv.lib.maintainers.raskin ];
     platforms = with stdenv.lib.platforms;
       linux ++ freebsd ++ gnu;
+    license = stdenv.lib.licenses.gpl3Plus;
   };
 }