Change the paths stored on the database

The paths in the database now are relative of the config BOOKS_PATH and COVER_PATH

For updating the database this query should be use:
for (var i = db.books.find(); i.hasNext(); ) {
        var book = i.next();
        db.books.update({_id: book["_id"]}, {$set: {path: book["path"].slice(6), cover: book["cover"].slice(7), coversmall: book["coversmall"].slice(7)}});
}

admin.go

@@ -166,7 +166,7 @@ func newHandler(w http.ResponseWriter, r *http.Request) {
 	}
 
 	if len(r.URL.Path) > len("/new/") {
-		http.ServeFile(w, r, r.URL.Path[1:])
+		http.ServeFile(w, r, NEW_PATH + r.URL.Path[len("/new/"):])
 		return
 	}