Bug in get_links tag

When calling it with before and between values, the latter isn’t inserted in case the link has no description.

It is a problem if (say) before='<strong>' and between='</strong>' – the latter will be missing, and all the rest of the list will be in bold.

A temporary fix is also to use after='</strong>'. The resulting page will have many unbalanced </strong> but will display correctly.