Add an auto-update to Transaction screen for first block #454
Description
With the introduction of Nano Contracts, many times a user will be following the Explorer to track a specific Nano Contract transaction right when it is mined to see if it completes successfully.
By adding a pooling and/or websocket mechanism to the transaction details screen, it can identify a new block has arrived and provide this feedback somehow to the user.
It may refresh the data, the whole page or maybe just add a card like the "Address Details" screen to inform the data being exhibited is obsolete.