Fix up subtitles which have a ', The' form. We no longer fix up such titles other than the primary title. The primary title uses the ", <prefix>" so the sort order can ignore prefixes words like 'The' or 'An'.

\tunestart
\showtune{$name}{$title}{$subtitle}{$fulltitle}{$tradition}{$composer}{$parts}{$tuneimagefile}
$notes

$history
\tuneend