This change aims to improve the framerate of the stabilizer visual feedback. - Perform delayed paint during `KisToolFreehandHelper::paint` (pointer event) and use a timer for backup. - Removed the `stabilizerDelayedPaintInterval` config option. - Added the `stabilizerDelayedPaint` config option for disabling the delayed painting,
Moved the paint code to be called during `KisToolFreehandHelper::paint` since this is how it's done for other smoothing methods and no smoothing. This shouldn't perform any worse than those. Removing the timer event dispatching might've caused some improvement too, but I haven't profiled for that.
Calling requestExplicitUpdateOutline during delayed paint is not needed anymore, but still needed during the timer. (It was needed because a delayed paint timer trigger can be after a pointer event, and not calling it would cause the outline to detach from the cursor if using a mouse.)