Fixed Travis install commands ordering
Fixed Travis install commands ordering

It was installing the package before installing Django. The package
triggers installation of the latest (stable) Django release. However
the test defines another version of Django, causing a re-install of
the specified version. By installing the correct version of Django
prior, only a single installation is required.

fusionbox/django-two-factor-auth,koleror/django-two-factor-auth,mathspace/django-two-factor-auth,mathspace/django-two-factor-auth,percipient/django-two-factor-auth,moreati/django-two-factor-auth,percipient/django-two-factor-auth,Bouke/django-two-factor-auth,Bouke/django-two-factor-auth,moreati/django-two-factor-auth,fusionbox/django-two-factor-auth,koleror/django-two-factor-auth