text: Thousands Protest Gaza Evacuation Plan JERUSALEM - Tens of thousands of Jewish settlers and their backers demonstrated in Jerusalem on Sunday against Prime Minister Ariel Sharon's plan to evacuate all settlements from Gaza and four West Bank enclaves in a rally held against a backdrop of assassination threats and warnings of civil war.    The withdrawal plan has upset the Israeli political scene since it was announced last year, turning Sharon's backers into opponents and detractors into supporters...