[FR] Support numbers such as "IV"

[NightMachinery]

Support numbers such as IV (4), II (2), etc.

[gweber2]

found this on the web for roman numbers:

def roman_to_int(s):
rom_val = {'I': 1, 'V': 5, 'X': 10, 'L': 50, 'C': 100, 'D': 500, 'M': 1000}
int_val = 0
for i in range(len(s)):
if i > 0 and rom_val[s[i]] > rom_val[s[i - 1]]:
int_val += rom_val[s[i]] - 2 * rom_val[s[i - 1]]
else:
int_val += rom_val[s[i]]
return int_val

Edit: The function seems to work but gives wrong output instead of error when given a wrong roman number.