Prepare ImageMagick differently in different OSes
Prepare ImageMagick differently in different OSes

carsonreinke/rmagick,tvon/rmagick,jonmartindell/rmagick,jonmartindell/rmagick,mockdeep/rmagick,btakita/rmagick,btakita/rmagick,tvon/rmagick,carsonreinke/rmagick,btakita/rmagick,rmagick/rmagick,antonifs/rmagick,mockdeep/rmagick,rmagick/rmagick,rmagick/rmagick,mockdeep/rmagick,mockdeep/rmagick,antonifs/rmagick,antonifs/rmagick,jonmartindell/rmagick,tvon/rmagick,carsonreinke/rmagick