Get an page by passing path and id *
function (path, id) {
            var hierachy = scope.tree.pathToPageArray(path);
            var parent = hierachy[ hierachy.length - 1 ];
            
            if (parent && parent.children && parent.children[ id ]) {
                return parent.children[ id ];
            } else if (path === '' && id === scope.tree.current.rootPageId) {
                return scope.tree.all[ id ];
            } 
            return null;
        }