Support for utf-8 characters

Hello, Thanks a lot for writing this great plugin.
I tried to use it to import some users with Arabic names and the csv didn’t encode the characters in the correct way.

I did some research and i fixed it by adding this line
fprintf($hnd, chr(0xEF).chr(0xBB).chr(0xBF));
before every ‘fputcsv’ function you have in the ‘User_Export_With_Meta’ class.

Thanks again for your efforts