BEIJING — For China’s small band of liberal intellectuals, this is the springtime of hope. Six days ago, one of their own, the writer and dissident Liu Xiaobo, was awarded the Nobel Peace Prize. On Monday, a score of Communist Party elders and scholars issued a scalding public attack on the government’s censorship regime. Since mid-August, Prime Minister Wen Jiabao has endorsed political reform on at least seven occasions, including on CNN and at the United Nations.