better cancelation messaging
0.8.3
- Added informative messages as to the root cause of a
TaskCancelation, e.g.
"TaskInstance 'doStuff' was canceled because .cancel() was explicitly called"
"TaskInstance 'doStuff' was canceled because .cancelAll() was explicitly called on the Task"
"TaskInstance 'doStuff' was canceled because it belongs to a 'restartable' Task that was .perform()ed again"