Update twocheckoutPayment.class.php

2CO has changed Pass Through Products parameters, so extensive changes were done in the code.
Update payment_twocheckout.po

To prepopulate the 2CO's shipping and billing pages country name should be in english.
gettext compiled translation
Docblock fix
Merge branch '2co-branch' of https://github.com/pilosus/webasyst-framework into develop