#173 if itunes modified mp3,then read error....

[CongTouZaiLai]

Add a mp3 file with itunes,change the artist field
value(itunes only supported id3v2).then read the artis
filed value with id3lib,error occured--error code.

example:
artist old value:梦醒时分
after set with itunes：梦醒时分1
read with id3lib:? .??

but some mp3 player can accurately read it。for
example:千千静听
（http://www.onlinedown.net/soft/8350.htm）