Blur Tool : add support of multicore CPU. Use new fast algorithm of simple...

Blur Tool : add support of multicore CPU. Use new fast algorithm of simple blur based on original implemntation from
libkimageeffect2 code (never released) written by Daniel M Duley.
Code have been ported to DImg and to support 1§ bits color depth image of course.
CImg dependency to Blur tool have been dropped.
Old and slow Guaussian blur algorithm have been removed
CCMAIL: veaceslav.munteanu90@gmail.com
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