ISIOLO, Kenya (Reuters) - Residents of a remote Kenyan town plan to demonstrate on Friday after a photo of U.S. presidential hopeful Barack Obama in Somali dress took centre stage in an increasingly acrimonious race for the White House. The picture, which appeared on a U.S. Web site, showed the Illinois senator donning a traditional white headdress and robes during a 2006 trip to Wajir in northeastern Kenya. Aides to Obama, whose late father was from Kenya, accused his rival Hillary Clinton's campaign of "the most shameful, offensive fear-mongering" of the election season so far after the picture was published....