Replaced the boolean properties in soc/models/request.py with a state property.
new : new Request
group_accepted : The group has accepted this request
completed : This request has been handled either following a creation of the role entity
rejected : This request has been rejected by either the user or the group
ignored : The request has been ignored by the group and will not give the user access to create the role
Patch by: Lennard de Rijk
Reviewed by: to-be-reviewed