Cleanup in org_app and replace ReferenceProperty with LinkProperty
Using LinkProperty allows the org to host their idea's list on
Melange through the Document system, and then specify the URL of that
document. This also makes it possible for the orgs to specify a
document that is not hosted on Melange.
Patch by: Sverre Rabbelier
Refactored the picker so that it is more generic
The picker now also works in the case the scope_path of the entity
should not be filtered on. Also, it is now easier to add new
functionality due to the fact that there is a seperate Field type
to handle it now.
Patch by: Sverre Rabbelier