BOUCHERVILLE, Que. — RONA inc. saw year-end sales drop 5.7%, from $4.44 billion in 2012 to $4.19 billion. Same-store sales fell 1.9%. The company’s fiscal year and fourth quarter in 2012 had one more week than in 2013. Excluding the extra week, the decrease reflects the closure of under-performing stores and a difficult year for most of the industry…