sortCache does not work

[saulsluz]

I tested in my application and in live demo. The bug is alive!

The steps:
1 . Perform any "filter"
2 . Perform any "sort"
3 . Remove the "filter"

The result is that you dont get all results again.
The feature "sortCache" inside applyFilters function not work properly.

A workaround is simple: just comment it.

                //if ($scope.sortOptions.predicate && $scope.sortCache && $scope.sortCache.predicate === $scope.sortOptions.predicate
                //    && $scope.sortCache.direction === $scope.sortOptions.direction) {
                //    $scope.filtered = $scope.sortCache.data.slice();
                //    sorted = true;
                //} else {
                    $scope.filtered = $scope._gridOptions.data.slice();
                //}

[AndreyChayko]

Issue closed as duplicate of #57