Hide preupg-content-creator questions

Here p-c-c is really used just as a tool, so its output is not relevant.

src/preupg_fupath.sh.skel

@@ -289,7 +289,7 @@ _preupg_fupath__mdef2module() {
     } >"$Tmp/answers"
     jat_dump__file -D "$Tmp/answers"
     jat__eval -h "create module: $m_name in group $m_group from $MdefFileNick" \
-        "preupg-content-creator <$Tmp/answers"
+        "preupg-content-creator <$Tmp/answers >/dev/null"
     newmod_path="$UPName/$m_group/$m_name"
 
     # add arbitrary values from $MdefFile