Added max version specifier in setup.py.
Added max version specifier in setup.py.

StanfordBioinformatics/xppf,StanfordBioinformatics/xppf,StanfordBioinformatics/loom,StanfordBioinformatics/loom,StanfordBioinformatics/xppf,StanfordBioinformatics/xppf,StanfordBioinformatics/loom,StanfordBioinformatics/loom