activeadmin/activeadmin — pull request #3472 by Bastes (2014-10-06 08:33:58+00:00)
Title: Documented the `:optional` option for belongs_to

I found the `:optional` option very useful for a project to expose nested resources in the global menu ; here's a short proposal to expose it in the documentation.

Thanks for all the good work in activeadmin, you rock!