Initial implementation of Runaway Takeoff Prevention (anti-taz)

Detects runaway pidSum values on takeoff and auto-disarms to prevent the "Tasmanian Devil" caused by incorrect props, wrong motor order/direction, incorrect flight controller orientation, etc.  After a successful takeoff and normal flight is detected the feature is disabled for the remainder of the battery.

src/test/unit/rc_controls_unittest.cc

@@ -50,6 +50,7 @@ extern "C" {
     #include "fc/rc_adjustments.h"
 
     #include "fc/rc_controls.h"
+    #include "fc/runtime_config.h"
 
     #include "scheduler/scheduler.h"
 }
@@ -57,6 +58,10 @@ extern "C" {
 #include "unittest_macros.h"
 #include "gtest/gtest.h"
 
+void unsetArmingDisabled(armingDisableFlags_e flag) {
+  UNUSED(flag);
+}
+
 class RcControlsModesTest : public ::testing::Test {
 protected:
     virtual void SetUp() {