tests: port of i18n test
tests: port of i18n test

* Moves tests authored by many different people from invenio package.

Co-authored-by: Jerome Caffaro <48b2bca20d17f7e0da978ba8575800a8c4a84744@cern.ch>
Co-authored-by: Lars Holm Nielsen <7eaffca9f7cd98839b5821d0d23e09ff764b82cd@cern.ch>
Co-authored-by: Sami Hiltunen <ebafb54bedf33e7dd12950a4634d6a0f6ba63e44@cern.ch>
Co-authored-by: Samuele Kaplun <2e218f779e12714c314fad8ebf6b3041daa21337@cern.ch>
Co-authored-by: Tibor Simko <c7116e45300b163846dc01f3ed02116e3f8ef7a5@cern.ch>
Signed-off-by: Jiri Kuncar <2bdffcb416fed3002465740d19a053a39918cbe5@cern.ch>

tiborsimko/invenio-base,inveniosoftware/invenio-base,inveniosoftware/invenio-base,tiborsimko/invenio-base