Fix successful response detection
Fix successful response detection

Server responds with {"status": "Ok"}, we were checking against "ok", case-sensitively.
Odd, though, that "status" can  be "Ok" or "error" - differing in capitalization...

translationexchange/tml-objc,translationexchange/tml-objc,translationexchange/tml-objc,translationexchange/tml-objc