Referrals v2.0

[dmtrjsg]

Context

• https://github.com/Joystream/atlas/issues/5047

Scope

Update reward calculation script to reflect the changes of the program (effective from 27th October)

• [ ] Referrer gets 5% of all referrals that their referred channel does (level 2 referrals)
• [ ] Referred channels will get 20% extra sign up bonus for using referral link