[Feature] Enhance Aave Support

[michael-spengler]

Ensure to just implement V2 methods and use V2 contracts

https://docs.aave.com/developers/the-core-protocol/protocol-overview

Especially the following features might be valuable for users of the DeFi Package:

• [ ] deposit/borrow/withdraw
• [ ] credit delegation
• [ ] liquidations
• [ ] using permit() for aTokens
• [ ] staking Aave token
• [ ] governance voting / delegating
• [ ] extracting data about user's positions, see lendingPool view methods (https://docs.aave.com/developers/the-core-protocol/lendingpool#view-methods) and protocol data provider (https://docs.aave.com/developers/the-core-protocol/protocol-data-provider)

[michael-spengler]

https://github.com/michael-spengler/decentralized-finance/blob/main/src/aave/aave.service.ts