Sample showing integration with SignalR

[kbaley]

This came up during a chat with someone asking for a simple sample of integrating NServiceBus with SignalR. Existing samples are:

• https://docs.particular.net/samples/near-realtime-clients/ which doesn't cover sending messages from a hub
• https://docs.particular.net/samples/showcase/on-premises/ which is quite large and requires more time to understand