In the Un Certain Regard category, which was created by honorary president Gilles Jacob to allow for some generational renewal in the festival’s programming grid, “Rafiki,” directed by newcomer filmmaker Wanuri Kahiu. The Nairobi-born director (b. 1980) had just one other feature-length film under her belt, “From a whisper,” before coming to Cannes, in the spirit of what was intended with this selection: brand-new, young