Move tests to TypeScript (coverage is still JS based)

ts_src/index.ts

@@ -17,6 +17,12 @@ export { TransactionBuilder } from './transaction_builder';
 export { BIP32Interface } from 'bip32';
 export { ECPairInterface, Signer, SignerAsync } from './ecpair';
 export { Network } from './networks';
-export { Payment, PaymentOpts, Stack, StackElement } from './payments';
+export {
+  Payment,
+  PaymentCreator,
+  PaymentOpts,
+  Stack,
+  StackElement,
+} from './payments';
 export { OpCode } from './script';
 export { Input as TxInput, Output as TxOutput } from './transaction';