Update query_row_named so its closure also takes a &Row instead of a Row

src/named_params.rs

@@ -38,12 +38,12 @@ impl Connection {
     /// Will return `Err` if `sql` cannot be converted to a C-compatible string or if the
     /// underlying SQLite call fails.
     pub fn query_row_named<T, F>(&self, sql: &str, params: &[(&str, &ToSql)], f: F) -> Result<T>
-        where F: FnOnce(Row) -> T
+        where F: FnOnce(&Row) -> T
     {
         let mut stmt = try!(self.prepare(sql));
         let mut rows = try!(stmt.query_named(params));
 
-        rows.get_expected_row().map(f)
+        rows.get_expected_row().map(|r| f(&r))
     }
 }