change parameter type of click event from arg_mouse to arg_click

include/nana/gui/widgets/checkbox.hpp

@@ -89,7 +89,7 @@ namespace drawerbase
 		std::size_t checked() const;       ///< Retrieves the index of the checkbox which is checked.
 		std::size_t size() const;
 	private:
-		void _m_checked(const arg_mouse&);
+		void _m_checked(const arg_click&);
 		void _m_destroy(const arg_destroy&);
 	private:
 		std::vector<element_tag> ui_container_;