Fix infinite loop in conda-skeleton
Fix infinite loop in conda-skeleton

fixes #391

The earlier code used to go in infinite recursion for some cases
because the same package name beening used again and again.

Signed-off-by: Harsh Gupta <c4bd8559369e527b4bb1785ff84e8ff50fde87c0@gmail.com>

rmcgibbo/conda-build,sandhujasmine/conda-build,ilastik/conda-build,dan-blanchard/conda-build,sandhujasmine/conda-build,rmcgibbo/conda-build,ilastik/conda-build,sandhujasmine/conda-build,mwcraig/conda-build,mwcraig/conda-build,ilastik/conda-build,shastings517/conda-build,dan-blanchard/conda-build,frol/conda-build,frol/conda-build,dan-blanchard/conda-build,rmcgibbo/conda-build,mwcraig/conda-build,shastings517/conda-build,shastings517/conda-build,frol/conda-build