feat: added initial version for rocket pool recipient

[cosminobol]

No description provided.

[samparsky]

let's store the rpStorage as an immutable variable as it won't change. Using it as a CWIA means we pay gas cost on every txn

[samparsky]

Is there a reason for this contract and why the below isn't gotten at runtime from the following the docs example? https://docs.rocketpool.net/developers/usage/contracts/contracts#interacting-with-rocket-pool

address public rocketPoolStorage;
  address public rocketPoolDeposit;
  address public rocketPoolMinipoolManager;
  address public rEth;