lexmark backend port

supported scanner list:
http://www.sane-project.org/sane-backends.html#S-LEXMARK

driver:
http://brain.umcs.lublin.pl/~rzookol/download/lexmark.lha

i dont have lexmark scanner so this driver is not tested, please test it and post result

[ Edited by zukow on 2011/1/11 0:28 ]