feat(Vault): simplify vault

[leonardishere]

Vault:

• removed strategies, debts, credits, queues, etc
• can deposit, withdraw, and pay claims
• can use claimsEscrow.sweep(weth.address, amount, vault.address) to return excess payment after claim is adjusted

Old contracts stored as contracts/future/_sol, old tests stored as test/future/_test_ts

Added more description to product token tests