added restriction to Python 2.x (see python-bioformats issue 9)
added restriction to Python 2.x (see python-bioformats issue 9)

jakirkham/python-javabridge,jakirkham/python-javabridge,jakirkham/python-javabridge,CellProfiler/python-javabridge,CellProfiler/python-javabridge,CellProfiler/python-javabridge,CellProfiler/python-javabridge,jakirkham/python-javabridge