Fixes #2847. CursesDriver doesn't processing response from task threading.

[BDisp]

Fixes #2847- On the PR #2786 I ruined this one, sorry. I also fixed the button text after finished the task.
Also fixes #2860 - When the pollTimeout == -1 the poll method seem to instruct it must wait until some action is detected. Setting the pollTimeout = 0, seem to fix the issue.

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[tig]

Nice work