Submitted by auditor0517, also found by 0x52, cccz, datapunk, kenzo, and pashov
Redeemer.redeem() for Element withdraws PT to wrong address.
This might cause a result of loss of PT.
According to the ReadMe.md, Redeemer should transfer external principal tokens from Lender.sol to Redeemer.sol.
But it transfers to the marketPlace and it would lose the PT.
Modify IElementToken(principal).withdrawPrincipal(amount, marketPlace); like this.
sourabhmarathe (Illuminate) confirmed
