add search (and aliases) to disease admin. closes #872

server/app/admin/diseases_admin.rb

@@ -1,8 +1,16 @@
 Trestle.resource(:diseases) do
+  collection do
+    Disease.eager_load(:disease_aliases)
+  end
+
   menu do
     item :diseases, icon: "fa fa-disease"
   end
 
+  search do |q|
+    q ? collection.where("diseases.doid ILIKE ? OR diseases.name ILIKE ? OR disease_aliases.name ILIKE ?", "%#{q}%", "%#{q}%", "%#{q}%") : collection
+  end
+
   scope :all, default: true
   scope :without_doid, -> { Disease.where(doid: nil) }
 
@@ -11,6 +19,9 @@
     column :id
     column :doid
     column :name
+    column :aliases do |disease|
+      disease.disease_aliases.map(&:name).join(", ")
+    end
   end
 
   # Customize the form fields shown on the new/edit views.