fix missing import in sdm.utils
Features: treat 1d bags as 1 x dim
Merge branch 'master' of github.com:dougalsutherland/py-sdm
Merge branch 'master' of github.com:dougalsutherland/py-sdm
Merge branch 'master' of github.com:dougalsutherland/py-sdm
Merge branch 'master' of github.com:dougalsutherland/py-sdm
Merge branch 'master' of github.com:dougalsutherland/py-sdm