Translate file size unit (#5651)
Translate file size unit (#5651)

Close #5649
Frenzie/koreader,poire-z/koreader,Markismus/koreader,koreader/koreader,poire-z/koreader,mihailim/koreader,NiLuJe/koreader,NiLuJe/koreader,koreader/koreader,Frenzie/koreader,Hzj-jie/koreader,mwoz123/koreader,pazos/koreader