Following a national trend, District officials have placed Wal-Mart squarely in the sights of pending legislation. The D.C. Examiner is reporting today that six of the City Council’s 13 members have signed onto legislation that would ban the construction or development of big box stores larger than 80,000 square feet if any more than 15 percent of their merchandise were tax-free. The legislation, sponsored by David Catania (I-At Large) would directly affect Wal-Mart and Target,…