Added leaf threshold temperatures

Added auto_cool and auto_heat for identifying the thresholds at which
leaf mode is enabled. Can be used in cool, heat, or range mode:

For example:

if ($infos->target->mode == "range") {
$leaf_temp=$infos->auto_heat." ".$infos->scale." - ".$infos->auto_cool."
".$infos->scale;
}
else if ($infos->target->mode == "cool") {
$leaf_temp=$infos->auto_cool." ".$infos->scale;
}
else if ($infos->target->mode == "heat") {
$leaf_temp=$infos->auto_heat." ".$infos->scale;
}
else {
$leaf_temp="N/A";
}