* collect rent from credit debit accounts
* collect rent from credit only account
* rent_collector now can deduct partial rent + no mem copy + improved design
* adding a test to test credit only rent
* add bank level test for rent deduction
* add test to check if hash value changes or not
* adding test scenario for lamport circulation
* collect rent from credit-debit account
* collect rent from credit only account
* improved design for rent collection
* only process if collected rent is non zero
* rent_collector now can deduct partial rent + no mem copy
* adding a test to test credit only rent
* add bank level test for rent deduction
* add test to check if hash value changes or not
* adding test scenario for lamport circulation
* combining rent debtors into credit only locks
* rename rent.rs to rent_calculator.rs
* add rent sysvar
* integrate rent_calculator with bank
* rent_calculator integration with genesis
* add test for rent sysvar