We should enable users to select a template that they want to generate a spec file with. Some people are trying to build PyPI packages for epel7 and the Fedora template, which is used by default, doesn't work for that chroot*. The same thing applies for gem2rpm.

*E.g.: https://copr-be.cloud.fedoraproject.org/results/iranzo/sarstats/epel-7-x86_64/00723020-python-sarstats/builder-live.log

**Also see issue: https://pagure.io/copr/copr/issue/207

***pyp2rpm templates can be found here: https://github.com/fedora-python/pyp2rpm/tree/master/pyp2rpm/templates. There should probably be a select in GUI with choices that corresponds to the available template names (an alternative is just to provide a text field, where a user can type in the template name. It's not that user-friendly but it is an option nevertheless).