Remove the trailing blank line in markdown text.
Remove the trailing blank line in markdown text.

The markup() function returns a string with an extra blank line (as
every HTML tag is outputted with a trailing newline). We don't really
want this, since it leaves a blank line in each <pre>, so check if
there's a newline and strip it away. This brings the look to how we had
things pre-markdown.

davidt/reviewboard,brennie/reviewboard,1tush/reviewboard,chipx86/reviewboard,bkochendorfer/reviewboard,1tush/reviewboard,davidt/reviewboard,bkochendorfer/reviewboard,KnowNo/reviewboard,sgallagher/reviewboard,bkochendorfer/reviewboard,custode/reviewboard,1tush/reviewboard,reviewboard/reviewboard,1tush/reviewboard,bkochendorfer/reviewboard,davidt/reviewboard,reviewboard/reviewboard,1tush/reviewboard,chipx86/reviewboard,1tush/reviewboard,beol/reviewboard,beol/reviewboard,sgallagher/reviewboard,custode/reviewboard,sgallagher/reviewboard,brennie/reviewboard,custode/reviewboard,beol/reviewboard,KnowNo/reviewboard,1tush/reviewboard,brennie/reviewboard,1tush/reviewboard,KnowNo/reviewboard,custode/reviewboard,1tush/reviewboard,KnowNo/reviewboard,chipx86/reviewboard,chipx86/reviewboard,reviewboard/reviewboard,davidt/reviewboard,reviewboard/reviewboard,beol/reviewboard,brennie/reviewboard,sgallagher/reviewboard