The latest trading updates from housebuilders reflect a market that is continuing to improve, providing growth opportunities.During the six months to December 2013, Barratt’s pre-tax profit rose 162% to £120.4 million and its first half completions (6,195) were the highest seen for five years. Redrow’s pre-tax profit soared 107% to £47.5 million over the same period with a 30% lift …