Deprecate abi-gen-wrappers (#2370)

* generate wrappers in @0x/contract-wrappers and delete abi-gen-wrappers

* trim exports from contract-wrappers

* separate contract-wrappers tests to get rid of dependency cycle

* remove dummy token contracts

* temporarily skip coordinator test until we can upgrade coordinator server

packages/0x.js/src/index.ts

@@ -33,7 +33,7 @@ export {
     ExchangeProtocolFeeCollectorAddressEventArgs,
     ExchangeProtocolFeeMultiplierEventArgs,
     ExchangeTransactionExecutionEventArgs,
-} from '@0x/abi-gen-wrappers';
+} from '@0x/contract-wrappers';
 
 export {
     ContractEvent,