The shock resignation of U.S. House Speaker John Boehner and his comments on Sunday that Congress will avoid a government shutdown this week potentially remove one source of investor anxiety as Wall Street gears up for a week heavy with economic data and commentary by Federal Reserve policymakers. Boehner said Friday he will step down from the speakership and leave the House at the end of October. On Sunday, he vowed that Congress will avoid a government shutdown, and he would push through as much unfinished legislation as possible before leaving at the end of October.