Email templates for microsites

I think we could discuss the merits of a few different options.

We should be able to just add an argument in [registration/urls.py](https://github.com/DirectEmployers/MyJobs/blob/email-templates-for-microsites/registration/urls.py#L13)
Or we could potentially do it in the activate_user decorator on the preceding line to the one linked.

[from_email is an optional argument to the password_reset view](https://github.com/django/django/blob/932d449f001a94aa5065cda652a442e4b1dd5352/django/contrib/auth/views.py#L150)