[#4420] Started on the Retainer's periods, only pending tests for now.

app/models/retainer_deliverable.rb

@@ -19,6 +19,10 @@ class RetainerDeliverable < HourlyDeliverable
     'R'
   end
 
+  def current_period
+    'TODO'
+  end
+
   def self.frequencies_to_select
     ValidFrequencies.collect {|f| [l("text_#{f}"), f]}
   end

app/views/contracts/show.html.erb

@@ -131,6 +131,7 @@
 
                     <table>
                       <%= show_field(deliverable, :frequency, :html_options => {:class => 'deliverable-frequency'}) if deliverable.retainer? %>
+                      <%= show_field(deliverable, :current_period, :html_options => {:class => 'deliverable-current-period'}) if deliverable.retainer? %>
                       <%= show_field(deliverable, :start_date, :format => :format_date, :html_options => {:class => 'deliverable-start-date'}) %>
                       <%= show_field(deliverable, :end_date, :format => :format_date, :html_options => {:class => 'deliverable-end-date'}) %>
                     </table>