Added default language pack (en-gb)

catalog/extension/total/coupon.php

@@ -0,0 +1,14 @@
+<?php
+// Heading
+$_['heading_title'] = 'Use Coupon Code';
+
+// Text
+$_['text_coupon']   = 'Coupon (%s)';
+$_['text_success']  = 'Success: Your coupon discount has been applied!';
+
+// Entry
+$_['entry_coupon']  = 'Enter your coupon here';
+
+// Error
+$_['error_coupon']  = 'Warning: Coupon is either invalid, expired or reached its usage limit!';
+$_['error_empty']   = 'Warning: Please enter a coupon code!';