Added default language pack (en-gb)

catalog/extension/payment/klarna_checkout.php

@@ -0,0 +1,13 @@
+<?php
+// Heading
+$_['heading_title']				   = 'Klarna Checkout';
+$_['heading_title_success']		   = 'Your Klarna Checkout order has been placed!';
+
+// Text
+$_['text_title']				   = 'Klarna Checkout';
+$_['text_basket']				   = 'Shopping Cart';
+$_['text_checkout']				   = 'Checkout';
+$_['text_success']				   = 'Success';
+$_['text_choose_shipping_method']  = 'Choose shipping method';
+$_['text_sales_tax']			   = 'Sales Tax';
+$_['text_newsletter']			   = 'Subscribe to our newsletter';