examples/demo_kinetics.py throws TypeError

[bryanwweber]

This is related to the review: https://github.com/openjournals/joss-reviews/issues/565

In trying to verify the functionality of the code, I ran into an error running examples/demo_kinetics.py. Running on Ubuntu 16.04, I installed ChemPy 0.6.5 from conda in a Python 3.6 environment, then cloned this repository, then

cd examples
python demo_kinetics.py

which results in

Traceback (most recent call last):
  File "demo_kinetics.py", line 37, in <module>
    import argh
ModuleNotFoundError: No module named 'argh'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "demo_kinetics.py", line 39, in <module>
    main()
  File "demo_kinetics.py", line 25, in main
    expr = f(*args, **kwargs)
TypeError: pseudo_irrev() got an unexpected keyword argument 'exp'

[bjodah]

Thanks, fixed in gh-89. (argh wansn't even used so I dropped to import)