NEW YORK -- On the eve of a possible U.S.-led war on Iraq, MSNBC is re-branding itself yet again, this time to reemphasize its hard-news lineage. So viewers tuning to MSNBC this week -- and lately there haven't been enough of those to satisfy the channel's bosses -- will notice immediate changes. MSNBC anchors have been told to stop using the "America's News Channel" slogan, which was introduced in April and was meant to convey that the network had a broad range of opinions, and instead refer to the channel as "NBC News on Cable 24 hours a day. [...]...