Parse magentic CC data from USB reader
var pattern=new RegExp("^\%B(\d+)\^(\w+)\/(\w+)\^\d+\?;\d+=(\d\d)(\d\d)\d+$");
var match = pattern.exec(card_data);
card_number = match[1];
first_name = match[3];
last_name = match[2];
exp_date = match[5] + "/" + match[4];