add *.json to datapats, should close #104

I don't really understand this section, I didn't build it. By what I see, _only_ the asterisk patterns are effective at including those types in the resultant distrib archive, and the rest do nothing. In any case, the below works with this change, and failed previously:

    python setup.py sdist
    pip install ..\dist\leo-5.0b1.zip