exa2pro/starpu-max: porting work to Maxeler DFE @ b110f4e08af02eaade6b5fb50276b59eee675477

Cédric Augonnet c41968e0c0 minor fix: remove a useless header		17 lat temu
..
ppm-downscaler.c	407c0fa3dc some systems don't have memalign	17 lat temu
ppm-downscaler.h	626b22ba6f introduce a new example "downscaler", no real stuff for the moment	17 lat temu
yuv-downscaler.c	c41968e0c0 minor fix: remove a useless header	17 lat temu
yuv-downscaler.h	846e608648 use StarPU to perform YUV downscaling (CPU only yet)	17 lat temu