[Django]-Getting the right dependency in Heroku

When using editable dependencies you have to define a tag or commit-hash.

Following your example:

-e git+https://github.com/merlinares/django-registration.git@3.1#egg=django-registration

or

-e git+https://github.com/merlinares/django-registration.git@40fee813ca444236da6d66f516b869fd8ebbe9cd#egg=django-registration