Queue info should be retrieved from server on some actions

[Eva Balycheva]

I think Zaqar UI in "Queues" panel should retrieve new queue info from server to show it correctly on these actions:
1. Clicking on expand button on the left from queue, which now shows current metadata and number of free messages.
2. Clicking on "Update" button on the right from queue, which now shows dialog for updating queue metadata with the current metadata for queue.

If it's possible, we should implement it in a way least affecting UI's responsiveness.
For example, when clicking on expand button near queue, the queue info can be expanded instantly, but update it's values a moment after. This will require two requests to zaqar: one for retrieving queue metadata, and one for retrieving queue stats. To make things even more quickier, these requests can be send simultaneously and not after each one.

If this seems complicated, perhaps as alternative solution we can just add "Refresh" button inside our "Queues" panel.