fixes in libdl/DL cmake

minor tweaks in pybullet OpenAI gym locomotion envs (connect to shared memory before going GUI/DIRECT)
bump up pybullet version to 1.3.6

examples/ThirdPartyLibs/Gwen/Macros.h

@@ -4,8 +4,10 @@
 #define GWEN_MACROS_H
 #include <stdlib.h>
 #include <stdarg.h>
-#if !defined(__APPLE__) && !defined(__OpenBSD__)
-#include <malloc.h>
+#if !defined(__APPLE__) && !defined(__OpenBSD__) && !defined(__FreeBSD__)
+	#include <malloc.h>
+#else
+	#include <stdlib.h>
 #endif //__APPLE__
 #include <memory.h>
 #include <algorithm>