Bug 571: play LOAD DATA INFILE the same way on the slave as it was on the master: 
if it was with IGNORE, do it with IGNORE,
if it was with REPLACE, do it with REPLACE,
and (the change) if it was with nothing, do it with nothing (not with IGNORE !!).
Bug 573: print a proper error message in case of duplicate entry in LOAD DATA INFILE
on the slave, i.e. a message where the keyname and key value appear :
'Duplicate entry '1' for key 1' and not 'Duplicate entry '%-.64s' for key %d'