Fixing #175; add an auto-subscribe and auto-favorite forum topic feature. Added 2 flags to the user profile. Added 2 functions that are called on the post post-save signal that auto-favorite and auto-subscribe the post creator if they have requested this service.

Dear {{ to_name }},

Your friend, {{ sender_name }}, wanted to send you a link to an 
interesting story found on {{ site_name }}.

{{ story_title|safe }}
http://{{ site_url }}{{ story_link }}

Thanks!
http://{{ site_url}}