Remove dummy Lithuanian translations.

All non-translated strings were "translated" as their English originals in
lt.po. This was just a artefact of the software used for translation and
wrong, so remove all these dummy translations.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@70483 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775