Add missing data into the notif. endpoint callback

Some information about the notification (ie: message_id and timestamp)
are currently not available for the application.

This change add them.

Partial implements blueprint notification-subscriber-server

Change-Id: I83e562725205fb270f6065fe1118c3c9865b2294
Add transport reconnection retries

When a rpc client try to make a RPC call and the server is unreachable
The rpc call hang until the server come back.

In most case this is the desired behavior.

But sometimes, we can prefer that the library raise an exception after a
certain number of retries.

This patch allow this.

Closes bug #1282639

Change-Id: I32086d0abf141c368343bf225d4b021da496c020