[#2280] Added a Billable header to the Timesheet plugin's report tables.

spec/lib/overhead_timesheet_hook_spec.rb

@@ -0,0 +1,7 @@
+require File.dirname(__FILE__) + '/../spec_helper'
+
+describe OverheadTimesheetHook, "#plugin_timesheet_views_timesheet_group_header" do
+  it 'should add a Billable column to the table' do
+    OverheadTimesheetHook.instance.plugin_timesheet_views_timesheet_group_header.should eql('<th>Billable</th>')
+  end
+end