Partially revert "Add language to installer path if it is missing"

Reverts some changes from 97e948abb4d277da3b57f85c65befe2ebb3f04dd.

Revert automatically adding the language code to filename:
http://gog.com/forum/general/introducing_the_beta_release_of_the_new_gogcom_downloader/post1483
Keep language in gameFile class because it may be useful later.