Liquidation Module for the common user

[JUSTISBEN]

Liquidation Module for the common user:

1. A rank-list UI which include the positions close to liquidation；
   The rank-list must include: Address, LTV (Loan to Value Ratio), Collateral, Debt, Amount;
2. A liquidation button；
3. When the user's position has negative account liquidity, then the liquidation button will be active, otherwise this button is inactive;
4. The liquidator can click the button to participate the liquidation;