Add counts properties
correct handling of class_attributes

subclasses were polluting the super class' attributes and
associations on load time
Only return a model instance of there was a body
Added method for finding grants for a user on a space
Added ref property on Grant model
Fix regexp and catch GoneError
Added update method to view
Added target_params option to Reference#search
added new payment auth error
added created_via property on contracts
Method for getting a linked account contact by its external id.
Added type property to app views.
added method on space-model to get debtor profile
Added handling of payment errors (402s)
updated payment overdue info on space
Added new operation to Grant model
Added the grant count property on the organization.
Added created_on on Grant model and excerpt on Item model
Added support for providing options to find_own_on_org_for_grant_list on Grant model
Updated methods on Grant model to support customizable fields