I don't know how to implement random in imath library for using imath.random() in script **and** hostlua.

Attached is the patch for this new imath functions:

`int(5010) = 5000 / int(-5010) = -5000`

frac(5010) = 10 / frac(-5010) = -10

ceil(5010) = 6000 / ceil(-5010) = -5000

floor(5010) = 5000 / floor(-5010) = -6000

round(5010) = 5000 / round(-5010) = -5000