FIX for displaying the Playlist in player(s)

The Wijering family of players use the 'displayheight' option as a flag as well as a value. It presents turns on the display of the playlist (even if set to 0). Its absence menas no playlist. When it was being set to 0 (zero) the "_wijering_flashvars" would chomp it and it would not make it to the otherside. This can be fixed by a small change to the comparison operator:
This:

 if (!$setting || $setting == 'default') {
            unset($defaults[$category][$key]);
          }

should be:

 if ($setting == '' || $setting == 'default') {
            unset($defaults[$category][$key]);
          }

due to the way PHP see "" and "0" and NULL as the same in logic operators

word