Page: add id field

database/pagedao.h

@@ -11,9 +11,9 @@ class PageDao
   public:
 	PageDao();
 	virtual bool exists(std::string page) const = 0;
-	virtual bool exists(int id) const = 0;
+	virtual bool exists(unsigned int id) const = 0;
 	virtual std::optional<Page> find(std::string name) = 0;
-	virtual std::optional<Page> find(int id) = 0;
+	virtual std::optional<Page> find(unsigned int id) = 0;
 	virtual std::vector<std::string> getPageList(QueryOption option) = 0;
 	virtual std::vector<std::string> fetchCategories(std::string pagename, QueryOption option) = 0;
 	virtual void deletePage(std::string page) = 0;