extract a common Request class
extract request class into own method in controllers
fold RequestGroup class into request_groups.rb
add class for hiding inaccessible requests
introduce the concept of permissions

if a user isn't permitted to create a request, they don't
see the request in the navigation list
at this point, everyone is still able to create any request
add content requester permission
change user stubbing in integration tests

use a hand-rolled stub instead of a mocha stub
prevent user w/o permission from creating requests