Breaks with matplotlib 2.1.0

[shukon]

Traceback (most recent call last):
  File "scripts/asapy", line 78, in <module>
    asapy.main(config, args_.max_algos, args_.only_fold)
  File "/home/shuki/asapy/asapy/asapy.py", line 274, in main
    footprints_plots = pa.get_footprints()
  File "/home/shuki/asapy/asapy/perf_analysis/perf_analysis.py", line 828, in get_footprints
    mpld3.save_html(fig, out_fn + ".html")
  File "/home/shuki/asapy/asapy_env/lib/python3.5/site-packages/mpld3/_display.py", line 453, in save_html
    fileobj.write(fig_to_html(fig, **kwargs))
  File "/home/shuki/asapy/asapy_env/lib/python3.5/site-packages/mpld3/_display.py", line 251, in fig_to_html
    figure_json=json.dumps(figure_json, cls=NumpyEncoder),
  File "/usr/lib/python3.5/json/__init__.py", line 237, in dumps
    **kw).encode(obj)
  File "/usr/lib/python3.5/json/encoder.py", line 198, in encode
    chunks = self.iterencode(o, _one_shot=True)
  File "/usr/lib/python3.5/json/encoder.py", line 256, in iterencode
    return _iterencode(o, 0)
  File "/home/shuki/asapy/asapy_env/lib/python3.5/site-packages/mpld3/_display.py", line 138, in default
    return json.JSONEncoder.default(self, obj)
  File "/usr/lib/python3.5/json/encoder.py", line 179, in default
    raise TypeError(repr(o) + " is not JSON serializable")
TypeError: array([0]) is not JSON serializable

quick fix: downgrade matplotlib
pip install matplotlib==2.0.2