Extract opening a comic from YACReaderLibrary to its own file

And send a new param `--readingListId` to tell YACReader that the comic is opened from a reading list.

YACReaderLibrary/library_window.h

@@ -313,7 +313,6 @@ public slots:
     void selectSubfolder(const QModelIndex &mi, int child);
     void checkEmptyFolder();
     void openComic();
-    void openComic(const ComicDB &comic);
     void createLibrary();
     void create(QString source, QString dest, QString name);
     void showAddLibrary();