As the Austrian capital honours the legacy of its dance king, the race is on to attract the most punters The music of Johann Strauss streams through Vienna like the stately Danube. Even the syllables of the composer's name beat out the rhythm of a waltz, as all Austrian dance teachers know. In their lessons, the words "Jo-hann Strauss" are often swapped in to replace the conventional "one, two, three" step count. Vie…