[#4182] Added an OverheadBudget to track a Deliverable's overhead.

db/migrate/005_create_overhead_budgets.rb

@@ -0,0 +1,16 @@
+class CreateOverheadBudgets < ActiveRecord::Migration
+  def self.up
+    create_table :overhead_budgets do |t|
+      t.decimal :hours, :precision => 15, :scale => 4
+      t.decimal :budget, :precision => 15, :scale => 4
+      t.references :deliverable
+      t.timestamps
+    end
+
+    add_index :overhead_budgets, :deliverable_id
+  end
+
+  def self.down
+    drop_table :overhead_budgets
+  end
+end