Roman numbers kata Given a positive integer number write a function returning its Roman numeral representation as a String.
Examples:
1=> I 20=> XX 300=> CCC 2=> II 30=> XXX 400=> CD 3=> III 40=> XL 500=> D 4=> IV 50=> L 600=> DC 5=> V 60=> LX 700=> DCC 6=> VI 70=> LXX 800=> DCCC 7=> VII 80=> LXXX 846=> DCCCXLVI 8=> VIII 90=> XC 900=> CM 9=> IX 100=> C 1000=> M 10=> X 200=> CC 1999=> MCMXCIX 2008=> MMVIII