Added default language pack (en-gb)

admin/extension/dashboard/sale.php

@@ -0,0 +1,17 @@
+<?php
+// Heading
+$_['heading_title']    = 'Total Sales';
+
+// Text
+$_['text_extension']   = 'Extensions';
+$_['text_success']     = 'Success: You have modified dashboard sales!';
+$_['text_edit']        = 'Edit Dashboard Sales';
+$_['text_view']        = 'View more...';
+
+// Entry
+$_['entry_status']     = 'Status';
+$_['entry_sort_order'] = 'Sort Order';
+$_['entry_width']      = 'Width';
+
+// Error
+$_['error_permission'] = 'Warning: You do not have permission to modify dashboard sales!';