Reorganize entities. Make scripts work from any directory.

packages/pipeline/src/entities/index.ts

@@ -0,0 +1,7 @@
+export { Block } from './block';
+export { ExchangeCancelEvent } from './exchange_cancel_event';
+export { ExchangeCancelUpToEvent } from './exchange_cancel_up_to_event';
+export { ExchangeFillEvent } from './exchange_fill_event';
+export { Relayer } from './relayer';
+export { SraOrder } from './sra_order';
+export { Transaction } from './transaction';