Support for PC platform (#12)

* improvements for cross-platform compiling

* moved tactility-core to libs/

* splitup improvements

* remove git/gitmodules from freertos

* better platformbetter platform checks

* added build scripts

* delete mbedtls

* re-add mbedtls

* fixes and improvements

* added pc build

* simplify build scripts

* revert build scrpit

* updated builds

* fix for pc

* fix for pc

* fix for build

libs/mbedtls/tests/suites/test_suite_timing.function

@@ -0,0 +1,57 @@
+/* BEGIN_HEADER */
+
+/* This test module exercises the timing module. Since, depending on the
+ * underlying operating system, the timing routines are not always reliable,
+ * this suite only performs very basic sanity checks of the timing API.
+ */
+
+#include <limits.h>
+
+#include "mbedtls/timing.h"
+
+/* END_HEADER */
+
+/* BEGIN_DEPENDENCIES
+ * depends_on:MBEDTLS_TIMING_C
+ * END_DEPENDENCIES
+ */
+
+/* BEGIN_CASE */
+void timing_get_timer()
+{
+    struct mbedtls_timing_hr_time time;
+
+    memset(&time, 0, sizeof(time));
+
+    (void) mbedtls_timing_get_timer(&time, 1);
+
+    /* Check that a non-zero time was written back */
+    int all_zero = 1;
+    for (size_t i = 0; i < sizeof(time); i++) {
+        all_zero &= ((unsigned char *) &time)[i] == 0;
+    }
+    TEST_ASSERT(!all_zero);
+
+    (void) mbedtls_timing_get_timer(&time, 0);
+
+    /* This goto is added to avoid warnings from the generated code. */
+    goto exit;
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
+void timing_delay(int fin_ms)
+{
+    mbedtls_timing_delay_context ctx;
+    int result;
+    if (fin_ms == 0) {
+        mbedtls_timing_set_delay(&ctx, 0, 0);
+        result = mbedtls_timing_get_delay(&ctx);
+        TEST_ASSERT(result == -1);
+    } else {
+        mbedtls_timing_set_delay(&ctx, fin_ms / 2, fin_ms);
+        result = mbedtls_timing_get_delay(&ctx);
+        TEST_ASSERT(result >= 0 && result <= 2);
+    }
+}
+/* END_CASE */