Update AutorecoveringConnection to call ShutdownListeners before reco…

[doswell]

…nnecting.

Re; #135

[michaelklishin]

I find it non-obvious how the (user-provided) hooks are recovered.

[michaelklishin]

I need to think if I'm 100% happy with this particular implementation of the idea in #135.

[doswell]

@michaelklishin I'd probably say "no not happy" I've worked on a more clear, and probably more importantly, more consistent implementation of calling the user hooks.
In short there is a ForwardingRecoveryListener" class where user hooks are added into, and which gets fired prior to the recovery starting. It also applies the same sync blocks that the existing delegate listeners use. I just have to get it up to git.
The hooks are also just maintained within AutorecoveringConnection and not added to the underlying delegate.
I'll try and get that up tomorrow

[michaelklishin]

@doswell thank you. One idea I had is simply subclassing ShutdownListener (to produce a marker class) so that we can tell a recovery shutdown hook from others so that they can be filtered out. How does that sound?

Alternatively we could use annotations but then I'm afraid this cannot be backported into stable.

[doswell]

I didn't see a need for the subclassing in terms of the shutdown listeners just notifying that a disconnect occurs. ie, keeping separate from #132. But I think the idea of subclassing may be useful for #132 in terms of having a RecoveryStartedListener / RecoveryCompletedListener which can register on the RecoveryListeners without needing API changes.

[michaelklishin]

Thank you for your time. There are some class responsibility and cosmetic things in this PRs that I disagree with but I think I understand the intent in #135 well enough now. I will look into an alternative PR for #135.