Add backward response for N3 account verification

[smallhive]

Is your feature request related to a problem? Please describe.

Using N3 accounts gives a powerful tool. But in case of VerifySignature fails (return false), the Node doesn't return a response to the client app.

For instance, for container removal. If a user tries to remove someone's container:

• VerifySignature returns false
• There is a log message in AIO:

error	container/process_container.go:172	delete container check failed	{"error": "auth container removal: verification script run resulted in false"}

But the client app still waits for the response. Eventually timeout.

Describe the solution you'd like

Return a clear response, the check failed