Merge pull request #1 from rt4tech/master

Pulling in commits from rt4tech
Added to Volunteer model

Added signup_date, contacted, and contact_date from issue #2 on
rt4tech/website, will add contacted_by next
Added contacted_by

Also set the default of contacted to false
NullBooleanField fix
contacted_date automatic setting
Added filtering by contacted_date
Merge pull request #5 from matthewsot/master

Added volunteer signup data.

Closes #2.