By Josef Adalian  CBS is showing a little love to "Accidentally on Purpose." The network has ordered five more episodes of the Jenna Elfman half-hour, insiders confirmed Tuesday. That's short of a full-season pickup but still a modest vote of confidence in the series. Critics were mixed in their reviews of "AOP," but viewership has been steady. It's been retaining between 80-90 percent of its "How I Met Your Mother" lead-in. Last night, it delivered its best ...