BundleUtilities: Work w/ non .app exes on Mac (#12034)

Also add a test of BundleUtilities including an exe,
some shared libs, a plugin, and a framework-style lib.

This test presently runs (and this functionality works)
on Linux, Mac and Windows.

For now, the framework-style lib is built as a plain old
shared lib because there is another yet-unresolved issue
with local frameworks without rpaths on the Mac.

Tests/BundleUtilities/framework.h

@@ -0,0 +1,17 @@
+
+#ifndef framework_h
+#define framework_h
+
+#ifdef WIN32
+# ifdef framework_EXPORTS
+#  define FRAMEWORK_EXPORT __declspec(dllexport)
+# else
+#  define FRAMEWORK_EXPORT __declspec(dllimport)
+# endif
+#else
+# define FRAMEWORK_EXPORT
+#endif
+
+void FRAMEWORK_EXPORT framework();
+
+#endif