Allowances

To place an order, allowances must be set by the funder address for the specified maker asset for the Exchange contract. When buying, this means the funder must have set a USDC allowance greater than or equal to the spending amount. When selling, the funder must have set an allowance for the conditional token that is greater than or equal to the selling amount. This allows the Exchange contract to execute settlement according to the signed order instructions created by a user and matched by the operator.