[enh] Allow to set env var for executed hooks in hooks_callback
[enh] Allow to set env var for executed hooks in hooks_callback

YunoHost/moulinette-yunohost,YunoHost/moulinette-yunohost,YunoHost/moulinette-yunohost,YunoHost/moulinette-yunohost,YunoHost/yunohost,YunoHost/yunohost,YunoHost/yunohost,YunoHost/yunohost,YunoHost/moulinette-yunohost