gettext: unescape quotation mark
gettext: unescape quotation mark

Fixes #2718.

apletnev/koreader,Frenzie/koreader,mwoz123/koreader,Hzj-jie/koreader,mihailim/koreader,NiLuJe/koreader,poire-z/koreader,pazos/koreader,Frenzie/koreader,koreader/koreader,houqp/koreader,koreader/koreader,poire-z/koreader,Markismus/koreader,robert00s/koreader,lgeek/koreader,NiLuJe/koreader