Restore the bottom paging links on 'Get users'.

They were removed as form elements cannot be nested, so the checkuser paging links being forms meant that the larger checkuser block form that covered the results to include the checkboxes next to each user / IP was truncated just after the results which split the form and user checkboxes effectively breaking the entire form. This would only happen if the results were paged and in the mean time removal was done so that a quick fix could be implemented.

Re-adding these could be done for non-IE browsers via the HTML form attribute on the user checkboxes so that modern browsers would be able to have the bottom paging links again. For this some kind of browser detection would be needed that would be reliable enough so that it could be known whether to or whether to not show the bottom paging links.