Make Lua C modules load dynamic libraries with global symbols

--- src/loadlib.c.orig	Tue Nov  6 11:24:02 2012
+++ src/loadlib.c	Tue Nov  6 11:24:41 2012
@@ -66,7 +66,7 @@ static void ll_unloadlib (void *lib) {
 
 
 static void *ll_load (lua_State *L, const char *path) {
-  void *lib = dlopen(path, RTLD_NOW);
+  void *lib = dlopen(path, RTLD_NOW | RTLD_GLOBAL);
   if (lib == NULL) lua_pushstring(L, dlerror());
   return lib;
 }