Reads nil for blank row

[jpmckinney]

FastestCSV.parse("\n\n\n")
# [[nil], [nil], [nil]]

CSV.parse("\n\n\n")
# [[], [], []]

fastest-csv/ext/csv_parser/parser.c

Line 83 in bc99d30

rb_ary_push(array, (index == 0 ? Qnil: rb_str_new(value, index)));