added stdint.h to compile igtlH264 on linux

Author: errollgarner

Source/VideoStreaming/igtlH264Encoder.cxx

@@ -44,6 +44,7 @@
  */
 #define _CRT_SECURE_NO_WARNINGS
 #include <stdio.h>
+#include <stdint.h>
 #include <string.h>
 #include <assert.h>
 #include <signal.h>