Preparation for timers

Currently directly using timing.c, plan to use callbacks later to loosen
coupling, but first just get things working.
diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index de517d6..ca11162 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -76,6 +76,10 @@
 #include "zlib.h"
 #endif
 
+#if defined(POLARSSL_TIMING_C)
+#include "timing.h"
+#endif
+
 #if defined(POLARSSL_HAVE_TIME)
 #include <time.h>
 #endif
@@ -815,6 +819,14 @@
     ssl_transform *transform_negotiate; /*!<  transform params in negotiation */
 
     /*
+     * Timers (WIP)
+     */
+#if defined(POLARSSL_TIMING_C)
+    struct hr_time time_info;
+    unsigned long time_limit;
+#endif
+
+    /*
      * Record layer (incoming data)
      */
     unsigned char *in_buf;      /*!< input buffer                     */