add ETH compatibility to AaveV2WrapV2Adapter

[bergben]

Adds the WETHGateway to the AaveV2WrapV2Adapter so that it behaves the same way as the CompoundWrapV2Adapter.

I thought ensuring behavior across integrations reduces some complexity

Rebasing could be a problem, that has to be researched further. I asked on the discord because there is some conflicting information:

• In the FAQ it says that Set tokens do not support rebasing tokens
• In the docs it says

Another caveat to be aware of in the current interaction of Set is that any asset that you want to include must not be a Rebasing token or one with a Transfer Fee associated with it. The issue here is that these token properties are not compatible with the contract assumptions of a Set being 100% collateralised at present.

• On Set protocol discord it was mentioned that
  the leverage module syncs on issuance

the wrap module would add support for tokens that don't fulfill the liquidity requirement

I tried to ask for more details on discord