fixes #287; bugfix: subrange checking is performed again

tests/compile/tmatrix1.nim

@@ -0,0 +1,19 @@
+discard """
+  output: "right proc called"
+"""
+
+type
+  TMatrixNM*[M, N, T] = object 
+    aij*: array[M, array[N, T]]
+  TMatrix2x2*[T] = TMatrixNM[range[0..1], range[0..1], T]
+  TMatrix3x3*[T] = TMatrixNM[range[0..2], range[0..2], T]
+
+proc test*[T] (matrix: TMatrix2x2[T]) =
+  echo "wrong proc called"
+
+proc test*[T] (matrix: TMatrix3x3[T]) =
+  echo "right proc called"  
+
+var matrix: TMatrix3x3[float]
+
+matrix.test