Add plugin link in README
Add plugin link in README

bookshelf/bookshelf,TinOo512/bookshelf,rbong/bookshelf,TinOo512/bookshelf,rbong/bookshelf,bookshelf/bookshelf,tgriesser/bookshelf,seegno-forks/bookshelf,tgriesser/bookshelf,jadengore/bookshelf,jadengore/bookshelf,seegno-forks/bookshelf,jadengore/bookshelf