allow substitution of a platform-specific MD5-sum command (OSX compatibility)
allow substitution of a platform-specific MD5-sum command (OSX compatibility)

ctuning/ck-env,ctuning/ck-env,ctuning/ck-env,ctuning/ck-env,ctuning/ck-env,ctuning/ck-env,ctuning/ck-env,ctuning/ck-env