Cleanup

Added missing method of TaskPool, reduced levels of log messages about
view resizing.
Refactor|Client|LogWidget: Apply TaskPool for wrapping entries

This is work-in-progress. Task pools are now used for preparing new
incoming log entries and also for rewrapping the existing cached
entries for a new widget content width.

Todo: Implement pruning of excess entries (when pools are idle).
Client|LogWidget: Canceling ongoing rewraps

It is no longer necessary to wait for an ongoing rewrap to finish.