Add service/method name to RpcError

[jcready]

Fixes #195

[timostamm]

Thank you for looking into all cases! I only have two nits.

[timostamm]

We are safe to make the argument required. interface RpcTransport requires both arguments - I think I just commented them out because my IDE complained about them being unused.

Suggested change

	clientStreaming<I extends object, O extends object>(method?: MethodInfo<I, O>/*, options: RpcOptions*/): ClientStreamingCall<I, O> {
	const e = new RpcError('Client streaming is not supported by grpc-web', GrpcStatusCode[GrpcStatusCode.UNIMPLEMENTED]);
	if (method) {
	e.methodName = method.name;
	e.serviceName = method.service.typeName;
	}
	throw e;
	clientStreaming<I extends object, O extends object>(method: MethodInfo<I, O>/*, options: RpcOptions*/): ClientStreamingCall<I, O> {
	const e = new RpcError('Client streaming is not supported by grpc-web', GrpcStatusCode[GrpcStatusCode.UNIMPLEMENTED]);
	e.methodName = method.name;
	e.serviceName = method.service.typeName;
	throw e;

[jcready]

I made this optional so that the previous unit tests would pass (it didn't pass in the MethodInfo). Making this optional was a smaller change, but I will make this required and update the unit test.

[timostamm]

Ah, I was unaware. Thanks for the update!

[timostamm]

Same here - safe to require the argument.

Suggested change

	duplex<I extends object, O extends object>(method?: MethodInfo<I, O>/*, options: RpcOptions*/): DuplexStreamingCall<I, O> {
	const e = new RpcError('Duplex streaming is not supported by grpc-web', GrpcStatusCode[GrpcStatusCode.UNIMPLEMENTED]);
	if (method) {
	e.methodName = method.name;
	e.serviceName = method.service.typeName;
	}
	throw e;
	duplex<I extends object, O extends object>(method: MethodInfo<I, O>/*, options: RpcOptions*/): DuplexStreamingCall<I, O> {
	const e = new RpcError('Duplex streaming is not supported by grpc-web', GrpcStatusCode[GrpcStatusCode.UNIMPLEMENTED]);
	e.methodName = method.name;
	e.serviceName = method.service.typeName;
	throw e;