Add NO_ABI_DECODER and ContractEvents

src/types.ts

@@ -15,6 +15,7 @@ export enum ZeroExError {
     InvalidJump = 'INVALID_JUMP',
     OutOfGas = 'OUT_OF_GAS',
     NoNetworkId = 'NO_NETWORK_ID',
+    NoAbiDecoder = 'NO_ABI_DECODER',
 }
 
 /**
@@ -340,6 +341,8 @@ export enum TokenEvents {
     Approval = 'Approval',
 }
 
+export type ContractEvents = TokenEvents|ExchangeEvents;
+
 export interface IndexedFilterValues {
     [index: string]: ContractEventArg;
 }