python setup.py install doesn't work

[vitorbaptista]

As noted by @marks in #22 (comment), you'd get "TemplateNotFound" when trying to run ckanext-mapviews when installing it through python setup.py install. Everything works fine if you run python setup.py develop.

This is probably because we're missing package_data in our setup.py. We must add the templates (and maybe something more) to it, so python knows what to copy from the source when installing the extension.

To learn how it works (and what needs to be done), check https://docs.python.org/2/distutils/setupscript.html#installing-package-data.