Description of problem:
I cannot get to package details for packages build in a group copr. All requests end with Error 500 : Internal Server Error 

Steps to Reproduce:
1. go to https://copr.fedorainfracloud.org/coprs/g/spice/nightly/packages/
2. click on a package (for ex spice-gtk)

Actual results:
 Error 500 : Internal Server Error
('coprs_ns.group_copr_package_icon', {'coprname': u'nightly', 'package_name': u'spice-gtk', 'group_name': u'spice'}, None) 

Expected results:
The package details show up