Merge branch 'feature/wdts' into 'master'

Feature/wdts

This adds two watchdogs to  esp-idf:

- An interrupt watchdog. Kicks in if the FreeRTOS timer interupt on either the PRO_CPU or (when configured) the APP CPU isn't called for a configurable time. Panics, displaying which CPU caused the problem and the registers that may lead to the offending code.
- A task watchdog. A task has to feed it every once in a while. If not, it will print the name of the offending tasks, as well as the tasks currently running on both CPUs, and optionally panic.

Also adds a panic reason to the panic call, as well as fixes the panic code a bit.

See merge request !148

components/freertos/include/freertos/task.h

@@ -2078,6 +2078,17 @@ TickType_t uxTaskResetEventItemValue( void ) PRIVILEGED_FUNCTION;
  */
 TaskHandle_t xTaskGetCurrentTaskHandle( void ) PRIVILEGED_FUNCTION;
 
+
+
+/*
+ * Return the handle of the task running on a certain CPU. Because of
+ * the nature of SMP processing, there is no guarantee that this
+ * value will still be valid on return and should only be used for
+ * debugging purposes.
+ */
+TaskHandle_t xTaskGetCurrentTaskHandleForCPU( BaseType_t cpuid );
+
+
 /*
  * Capture the current time status for future reference.
  */