Random module: fix links, improve header.
Random module: fix links, improve header.

singularperturbation/Nim,singularperturbation/Nim,mbaulch/Nim,tulayang/Nim,dom96/Nim,tulayang/Nim,jfhg/Nim,jfhg/Nim,russpowers/Nim,mbaulch/Nim,jfhg/Nim,singularperturbation/Nim,dom96/Nim,haiodo/Nim,dom96/Nim,tulayang/Nim,haiodo/Nim,tulayang/Nim,mbaulch/Nim,tulayang/Nim,singularperturbation/Nim,singularperturbation/Nim,mbaulch/Nim,dom96/Nim,jfhg/Nim,russpowers/Nim,tulayang/Nim,dom96/Nim,mbaulch/Nim,singularperturbation/Nim,haiodo/Nim,singularperturbation/Nim,haiodo/Nim,haiodo/Nim,russpowers/Nim,mbaulch/Nim,jfhg/Nim,dom96/Nim,dom96/Nim,haiodo/Nim,mbaulch/Nim,russpowers/Nim,russpowers/Nim,jfhg/Nim,russpowers/Nim,haiodo/Nim,jfhg/Nim,russpowers/Nim