Changes from MusiXTeX 126 to 127: * introduced \meterN, \xxtuplet * introduced \nqqb \nqqh \nqqqb \nqqqh abbreviations and synonyms \nqql \nqqu \nqqql \nqqqu * introduced \hap, \happ analogous to \qap, \qapp * introduced \hbsk analogous to \hsk * introduced \bqsk, \bhsk, \btsk analogous to \qsk, \hqsk, \tqsk * eliminated \ds@oup