Updated variables and fixed errors in template for production settings.

1. Changed template variable for ALLOWED_HOSTS setting to allowed_hosts.
2. email addresses for DEFAULT_FROM_EMAIL and SERVER_EMAIL to be set
   from a single variable rather than separate variables for username
   and domain name.
3. SITE_TITLE variable is now a unicode string.
4. Removed single quotes from SHOW_PHOTOS and SHOW_YEARLIST settings
   since these will be rendered as booleans.