(Reuters) - President Barack Obama on Tuesday will outline steps his administration is taking to revamp U.S. export restrictions on defense and high-tech goods, which is expected to lead to thousands of less sensitive items being decontrolled, senior administration officials said. "We've done this fundamentally for national security reasons so that we can ... focus our resources on protecting the most critical technologies," one of the senior officials told reporters at a briefing. The initiative, which already has been one year in the making, responds to frustration felt by U.S. defense and high-tech companies, who say export controls that date...