ENH: add missing files

Tests/OutOfSource/OutOfSourceSubdir/testlib.cxx

@@ -0,0 +1,6 @@
+#include "testlib.h"
+
+float TestLib()
+{
+  return 1.0;
+}

Tests/OutOfSource/OutOfSourceSubdir/testlib.h

@@ -0,0 +1,11 @@
+#ifdef _WIN32
+#  ifdef testlib_EXPORTS
+#    define CM_TEST_LIB_EXPORT  __declspec( dllexport )
+#  else
+#    define CM_TEST_LIB_EXPORT  __declspec( dllimport )
+#  endif
+#else
+#  define CM_TEST_LIB_EXPORT 
+#endif
+
+CM_TEST_LIB_EXPORT float TestLib();