cplex bug when setting paramter in solve_problem
cobra.io.mat dict construction is its own function

The create_mat_dict function may be useful when using sosmethig other
than scipy to write the mat file. The dict created contains vectors
matching the structure of the MATLAB COBRA toolbox struct.
README.md points to github site

Replaces the link to the older sourceforge site.
load_matlab_model reads subsystem
Improve setup.py on MacOS X

Running bdist_wheel will now append additional tag versions
automatically. Additionally, warnings for unused functions in clang are
now silenced to highlight other wanings which may signal issues.
update VERSION file on sdist/bdist_wheel