Add tablesorter-hasChildRow
If the last pager row has any child rows, they are now included
Add "filtered" css definition to every theme to hide content
Add tablesorter API section to docs. Make assorted corrections to docs &
cleanup. Update & consolidate jQuery UI accordion code. Updated some
scripts to use the correct version number (v2.15, not v2.14.6).
Exclude group-header class in filter widget
Exclude cssChildRow class in grouping widget
Change calculation of colspan in grouping widget
Add !important for group-hidden class