task::status responses remain static

[smk762]

I noticed that the response for zhtlc coin initialization once a coin has been activated remains static, i.e. if balance changes after activation completes, the balance at time of activation is still returned from the task::enable_z_coin::status request. This also applies to the returned current_block value.

It would be nice if the status returned live values for balance and block_height for any coins which include a task::status method, or any other similar method returning values which change after task completion.

Originally posted by @smk762 in #1957 (comment)