fix after merge with roberm branch: added 'using isinf/isnan' on apple; encapsulate isnan/isinf logic into function
fix after merge with roberm branch: added 'using isinf/isnan' on apple; encapsulate isnan/isinf logic into function

git-svn-id: c3edda122e248ef33995da003806c930f62b9468@942 31904243-a364-42ac-a3db-9305396518ba

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