When testing for wsgi script, use the appropriate setting.

In https://github.com/Wtower/ansible-django-deploy/blob/v0.1.3/tasks/main.yml#L5 

    local_action: stat path={{ conf.dev_path }}/index.wsgi

the test should check for the file from the same setting in https://github.com/Wtower/ansible-django-deploy/blob/v0.1.3/templates/vhost.conf.j2#L3

    WSGIScriptAlias / {{ conf.host_path }}/{{ conf.wsgi_script| default('index.wsgi') }}
