function stripBom(utf8String) {
    if (utf8String.charCodeAt(0) === 0xfeff) {
        return utf8String.substr(1);
    }
    return utf8String;
}
Given an UTF8 string, return a version of this string without the first byte if it corresponds
  to the Byte Order Mark
@param {String}  utf8String the string to strip
@return {String}