Uses wrong database when GeoDjango is in use

[AstraLuma]

If BUILD_WITH_GEO_LIBRARIES is set, the wrong database engine is used.

My work-around is:

django_heroku.settings(locals())

if DATABASES['default']['ENGINE'] in ('django.db.backends.postgresql', 'django.db.backends.postgresql_psycopg2'):
    DATABASES['default']['ENGINE'] = 'django.contrib.gis.db.backends.postgis'
elif DATABASES['default']['ENGINE'] == 'django.db.backends.sqlite3':
    DATABASES['default']['ENGINE'] = 'django.contrib.gis.db.backends.spatialite'

[sigmavirus24]

I would happily merge a pull request that fixes this @astronouth7303

[raelmax]

I've open a pull request to fix this issue: #36