Make gif and pnm tests dependent on their test dirs and libraries being found
Make gif and pnm tests dependent on their test dirs and libraries being found

micler/oiio,lgritz/oiio,cwilling/oiio,bdeluca/oiio,cwilling/oiio,micler/oiio,YangYangTL/oiio,lgritz/oiio,lgritz/oiio,OpenImageIO/oiio,sambler/oiio,sambler/oiio,micler/oiio,YangYangTL/oiio,lgritz/oiio,cwilling/oiio,mcanthony/oiio,scott-wilson/oiio,YangYangTL/oiio,micler/oiio,mcanthony/oiio,bdeluca/oiio,OpenImageIO/oiio,scott-wilson/oiio,cwilling/oiio,mcanthony/oiio,sambler/oiio,mcanthony/oiio,sambler/oiio,bdeluca/oiio,scott-wilson/oiio,YangYangTL/oiio,OpenImageIO/oiio,bdeluca/oiio,OpenImageIO/oiio,scott-wilson/oiio