Use Translation classes consistently

We're moving the code for the phases translation class to the same place
in the code the other translation classes are: right after including the
Globalizable module.

app/models/budget/phase.rb

@@ -9,6 +9,17 @@ class Budget
     translates :summary, touch: true
     translates :description, touch: true
     include Globalizable
+
+    class Translation
+      before_validation :sanitize_description
+
+      private
+
+        def sanitize_description
+          self.description = WYSIWYGSanitizer.new.sanitize(description)
+        end
+    end
+
     include Sanitizable
 
     belongs_to :budget
@@ -99,15 +110,5 @@ class Budget
       def in_phase_or_later?(phase)
         PHASE_KINDS.index(kind) >= PHASE_KINDS.index(phase)
       end
-
-    class Translation < Globalize::ActiveRecord::Translation
-      before_validation :sanitize_description
-
-      private
-
-        def sanitize_description
-          self.description = WYSIWYGSanitizer.new.sanitize(description)
-        end
-    end
   end
 end