refactor: distribute fees to all bonded validators

[julienrbrt]

ref: #39

Not rewarded based on validators uptime, as validators are slashed if down anyway.

[giunatale]

eventually we'll want to exclude validators that are offline from rewards though, see #38

[julienrbrt]

eventually we'll want to exclude validators that are offline from rewards though, see #38

yes, the logic here was for the provider. we will need to wait about implementing epoch based payout to check that (otherwise it is too much traffic).

I was jokingly saying to @tbruyelle that doing so does incentivize other validators to DOS their fellow validators.
Unless we design it that the fees per block are fixed per validators, and not fixed as a whole and shared with the active validators.