[lang] Add a couple of plurals (#8028)
[lang] Add a couple of plurals (#8028)

Reported by @ichnilatis-gr , see https://www.mobileread.com/forums/showthread.php?p=4140493#post4140493 and following.
koreader/koreader,Frenzie/koreader,NiLuJe/koreader,Frenzie/koreader,poire-z/koreader,poire-z/koreader,NiLuJe/koreader,koreader/koreader