gui: Make framerate configurable

Default framerate is 30 FPS

Change-Id: Ia05357663905a3babecb95b1e3531ae45fc854c5
diff --git a/gui/objects.hpp b/gui/objects.hpp
index 89cb742..e965255 100755
--- a/gui/objects.hpp
+++ b/gui/objects.hpp
@@ -49,6 +49,10 @@
 #define TW_H_OFFSET 0
 #endif
 
+#ifndef TW_FRAMERATE
+#define TW_FRAMERATE 30
+#endif
+
 class RenderObject
 {
 public: