Fix crash when searching CDDB in Japanese locale

A string in the Japanese translation swapped an integer and string
format string in a printf-formatted string. This caused a crash at
runtime. Use the positional syntax of gettext to substitute the correct
variable into the string.

http://www.gnu.org/software/gettext/manual/gettext.html#c_002dformat-Flag
https://bugs.launchpad.net/ubuntu/+source/easytag/+bug/642556