Merge pull request #47 from garrettlord/btgaffor

lots of stuffs (check commit log)
adds poll model & controller, integrates into group page for admins
adds poll response model and interaction
bug fix
bug fix
bug fix
added debug logging to twilio helper
bug fixing
bug fixing
bug fixing
more debug statements
more debug statements
remakes text_message model / validation
bug fix
more debug statements
bug fix
bug found
fixes sending poll question via text
restricts poll viewing to group admins
bug fix