[CIP] Add USDT Omnipool

This vote is to add support for a USDT Omnipool. If this vote is to pass the next steps would be:

• Deciding which Curve pools to whitelist [CAP]
• Deciding the initial liquidity allocation weights [LAV]

Before voting please read the full proposal on Discourse: https://gov.conic.finance/t/cip-add-usdt-omnipool/98?u=bb8