implement all DLL exports (as TODOs)

Now we can use our own compiled LEGO1.LIB rather than one generated from the original. Also implements a script that tests them to help ensure future commits don't break them.

LEGO1/mxdirectdraw.cpp

@@ -0,0 +1,22 @@
+#include "mxdirectdraw.h"
+
+// OFFSET: LEGO1 0x1009e7f0
+int MxDirectDraw::FlipToGDISurface()
+{
+  // TODO
+  return 0;
+}
+
+// OFFSET: LEGO1 0x1009d570
+int MxDirectDraw::GetPrimaryBitDepth()
+{
+  // TODO
+  return 0;
+}
+
+// OFFSET: LEGO1 0x1009e6a0
+int MxDirectDraw::Pause(int)
+{
+  // TODO
+  return 0;
+}