Remove conditional compilation for GetImageChannelDepth, GetImageChannelExtrema, GetImageChannelMean, GetImageHistogram, GetImageQuantumDepth. These methods are available in all supported versions of IM.
Remove conditional compilation for GetImageChannelDepth, GetImageChannelExtrema,
GetImageChannelMean, GetImageHistogram, GetImageQuantumDepth. These methods are available in all supported versions of IM.

chand3040/Rmagic,prognostikos/rmagick,tvon/rmagick,mockdeep/rmagick,rmagick/rmagick,mockdeep/rmagick,jonmartindell/rmagick,carsonreinke/rmagick,jonmartindell/rmagick,mockdeep/rmagick,apecherin/rmagick,btakita/rmagick,rmagick-temp/rmagick,rmagick-temp/rmagick,rmagick-temp/rmagick,carsonreinke/rmagick,tvon/rmagick,mockdeep/rmagick,btakita/rmagick,antonifs/rmagick,tvon/rmagick,modulexcite/rmagick,jonmartindell/rmagick,btakita/rmagick,prognostikos/rmagick,carsonreinke/rmagick,chand3040/Rmagic,antonifs/rmagick,pecha7x/rmagick,antonifs/rmagick,rmagick/rmagick,rmagick/rmagick,modulexcite/rmagick,apecherin/rmagick,pecha7x/rmagick,chand3040/Rmagic,prognostikos/rmagick