Borrowed table sort specifications, or null when sorting is disabled/unavailable. Apply changed specs to your data and clear SpecsDirty.
Sorting: call TableGetSortSpecs() to retrieve latest sort specs for the table. null when not sorting. When 'sort_specs->SpecsDirty == true' you should sort your data. It will be true when sorting specs have changed since last call, or the first time. Make sure to set 'SpecsDirty = false' after sorting, else you may wastefully sort your data every frame!
Functions args 'int column_n' treat the default value of -1 as the same as passing the current column index.
get latest sort specs for the table (null if not sorting). Lifetime: don't hold on this pointer over multiple frames or past any subsequent call to BeginTable().
Get the current table sorting specifications.