Add `Orchestra\Html\Table\Grid::paginated()` helper method to access pagination state for current table.

Signed-off-by: crynobone <crynobone@gmail.com>
Improve docblock and code consistency.

Signed-off-by: crynobone <crynobone@gmail.com>
Add testcase for meta data.

Signed-off-by: crynobone <crynobone@gmail.com>