UNITED NATIONS (Reuters) - The international response to a catastrophic tsunami in Asia has been quick and generous, a senior U.N. official said on Tuesday, playing down his earlier comments that wealthy nations were stingy. U.N. Emergency Relief Coordinator Jan Egeland rowed back from statements he made on Monday after an annoyed Secretary of State Colin Powell said Washington was "the greatest contributor to international relief efforts in the world." "The United States is not stingy," Powell told CNN's "American Morning" program. Egeland, a Norwegian, pleaded at a Monday news conference for individuals and governments around the world to respond...