require errormsg to be specified before file.

tests/iter/titer4.nim

@@ -1,10 +1,8 @@
 discard """
+  errormsg: "iterator within for loop context expected"
   file: "titer4.nim"
   line: 7
-  errormsg: "iterator within for loop context expected"
 """
 # implicit items/pairs, but not if we have 3 for loop vars:
 for x, y, z in {'a'..'z'}: #ERROR_MSG iterator within for loop context expected
   nil
-
-