Add project_urls so that PyPI will show GitHub stats.
Add project_urls so that PyPI will show GitHub stats.

pallets/flask,fkazimierczak/flask,drewja/flask,pallets/flask,mitsuhiko/flask,fkazimierczak/flask,drewja/flask,drewja/flask,fkazimierczak/flask,pallets/flask,mitsuhiko/flask