* glom/print_layout/canvas_layout_item.[h|cc]:
Moved get_canvas_table_cell_child() here from CanvasPrintLayout.
create_canvas_item_for_layout_item(): Move the table-child creation
code into add_portal_rows_if_necessary().
* glom/print_layout/canvas_print_layout.[h|cc]: fill_with_data_portal():
Add rows, up to the maximum, according to the number of database rows.
* glom/print_layout/print_layout_utils.cc: create_standard():
Set a simple default height for one row, but set a min of 1 and a max
of 100 so it will expand later.