add graduated filter examples
-rw-r--r-- 320 GNUmakefile
-rw-r--r-- 50307 flat.xcf
-rw-r--r-- 1243 gimp-xcf-png.scm
-rw-r--r-- 4595 graduated-filter_4.00_00_10_00_00.pp3
-rw-r--r-- 4595 graduated-filter_4.00_00_25_00_00.pp3
-rw-r--r-- 4595 graduated-filter_4.00_00_50_00_00.pp3
-rw-r--r-- 4596 graduated-filter_4.00_45_25_00_00.pp3
-rw-r--r-- 4606 vignette-filter_4.00_00_50.pp3
-rw-r--r-- 4606 vignette-filter_4.00_50_00.pp3
-rw-r--r-- 4607 vignette-filter_4.00_50_50.pp3
-rw-r--r-- 4608 vignette-filter_4.00_50_99.pp3
-rw-r--r-- 4608 vignette-filter_4.00_99_50.pp3