HelloWorld Example Ignores `Initialise` Result

[ilivewithian]

The hello world examples currently have the code:

await subscriber.Initialise(new[] {Assembly.GetExecutingAssembly()}))
await subscriber.ListenForMessages(tokenSource);

It should be more like:

if (await subscriber.Initialise(new[] {Assembly.GetExecutingAssembly()}))
{
    await subscriber.ListenForMessages(tokenSource);
}

All examples and relevant docs will need updating to reflect this improvement.