[#4182] Show the total Labor and Overhead values on the Contract details page.

app/models/deliverable.rb

@@ -32,7 +32,15 @@ class Deliverable < ActiveRecord::Base
       write_attribute(:total, v)
     end
   end
-  
+
+  def labor_budget_total
+    labor_budgets.sum(:budget)
+  end
+
+  def overhead_budget_total
+    overhead_budgets.sum(:budget)
+  end
+
   if Rails.env.test?
     generator_for :title, :method => :next_title