compiling all tests after some reorganization

test/set/function_set_post_pre_post_error.cpp

@@ -0,0 +1,15 @@
+
+#include <boost/contract/free_function.hpp>
+
+// Test post cannot be set twice (not even after pre) for free functions
+// (member functions use same setter objects, so no need to test those too).
+
+int main() {
+    auto c = boost::contract::free_function()
+        .postcondition([&] {})
+        .precondition([&] {})
+        .postcondition([&] {}) // Error.
+    ;
+    return 0;
+}
+