Improve the load time of the ministers page

From 5 to 2 seconds so that smoky tests don't fail.

https://www.pivotaltracker.com/story/show/46985989

Before

    Completed 200 OK in 4485ms (Views: 3353.1ms | ActiveRecord: 222.8ms)

After

    Completed 200 OK in 1899ms (Views: 1498.6ms | ActiveRecord: 133.3ms)


Further improvements will require digging into the translations in globalize3 to see if we can eager load the translations for people, through the role/role appointment.