Filter placement on working properly with dt2 with Beta0.9

[rrbrandolino-web]

In migrating to dt2 and yadcf beta 0.9 I found that the filters were not being added to the right header row.

changing lines starting as 3278 as follows seems to correct the issue with the filter placement.

if (settingsDt?.oApi?._fnGetUniqueThs !== undefined) {
unique_th = settingsDt.oApi._fnGetUniqueThs(settingsDt);
} else {
// unique_th = oTable?.table().header?.structure()[0];
// unique_th = unique_th.map(obj => obj.cell);
/ Rather than assume the filter goes in row 0 assume the last row, this seems to match the dt1.x behavior better rrbrand@usibm.com*/
unique_th = oTable.columns().header();
}

I still need to figure out the handling on the order arrows.