Tableselect table types with '#multiple' => FALSE do not work

Hello there,

It's been brought to my attention that tableselect type tables do not show the radio buttons when '#multiple' => FALSE is provided as an option in the array.

I have attached a quick module (based on one of the 'Example' modules https://drupal.org/project/examples) with a table populated using these options which can be accessed from /examples/tableselect_example when installed. If you switch to different themes you will see that the table renders the radio buttons, however does not with the Bootstrap theme.

Upon removing the option from the tableselect form element (allowing multiple select) there are no issues.