Fees collection

Protocol collects following fees:

• Interest rate fee, when user close credit account, or it's liquidated
• Liquidation fee, if account was liquidated
• Withdraw fee, when user removes liquidity

The fees remain in the pool, instead, the DAO treasury receives the pool's LP tokens. The protocol has a feature to leave part of the fees in the pool, thereby increasing the price of diesel tokens, that is, increasing the APY of the pool.