fix issues with std::vector<bool> overload in STL (fixes #216)
diff --git a/example/example17.ref b/example/example17.ref
index 55e47a6..cc271f3 100644
--- a/example/example17.ref
+++ b/example/example17.ref
@@ -8,3 +8,4 @@
 VectorInt[0, 99, 2, 3]
 VectorEl[El{1}, El{2}]
 VectorEl[El{1}, El{2}]
+VectorBool[1, 0, 1, 0, 1, 0, 1, 0, 1, 0]