Renders out the column headers for the grid, including links (where appropriate) to control column sorting.
The object that provides access to bean and data models, which is typically the enclosing Grid component.
Optional output parameter that stores the current column index.
If true, then the CSS class on each <TH> element will be omitted, which can reduce the amount of output
from the component overall by a considerable amount. Leave this as false, the default, when you are leveraging
the CSS to customize the look and feel of particular columns.
Where to look for informal parameter Blocks used to override column headers. The default is to look for such
overrides in the GridColumns component itself, but this is usually overridden.
If not null, then each link is output as a link to update the specified zone.
Returns null or "true", depending on whether the Grid is rendering for in-place updates or not ("true"
means in-place updates). The affects whether the data-inplace-grid-links attribute will be rendered or not.