[zeroex/ordervalidator] off-chain validation ignores nested asset data

[jalextowle]

Overview

The ordervalidator.BatchOffchainValidation function is used to provide a preliminary form of validation that should filter out orders that Mesh obviously cannot support. As of right now, staticcall asset data has been considered an "unsupported" asset data type. This order validation logic does not consider the contents of multi-asset data's nested asset data, which causes the logic to accept orders with multi-asset data that contains staticcall asset data.

Expected Behavior

Mesh rejects an order with multi-asset data that contains unsupported asset data.

Actual Behavior

Mesh accepts all MAP orders that are considered valid by the DevUtils contract.