Priority    Description
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Low         Parallelize different face detection operations

Low         Fix the redraw artifacts made when dragging and resizing face items.

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TODO list for post-GSoC 2019 on backend of face recognition:
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High 		Reinvestigate every options and combinations in facescan settings           ==> DONE

High 		Simplify facescan dialog (e.g. removing this dialog and place all widget
			in the bottom of people left sidebar tab, as for similarity tab for ex)     ==> DONE

Medium 		Implement feature to allow 128-D face embedding vectors to be computed
			only once, and when detected face bounding box is modified.
			(That feature seems already existed in FaceScanSettings::alreadyScannedHandling, but not implemented in the right way)