raise task priority and make it configurable (#9)

Author: h3ndrik

src/SnapConfig.h

@@ -63,3 +63,7 @@
 #ifndef RTOS_STACK_SIZE 
 #   define RTOS_STACK_SIZE 10 * 1024
 #endif
+
+#ifndef RTOS_TASK_PRIORITY
+#   define RTOS_TASK_PRIORITY 2
+#endif

src/api/SnapProcessorRTOS.h

@@ -41,7 +41,7 @@ class SnapProcessorRTOS : public SnapProcessor {
 
  protected:
   const char *TAG = "SnapProcessorRTOS";
-  cpp_freertos::Task task{"output", RTOS_STACK_SIZE, 1, task_copy};
+  cpp_freertos::Task task{"output", RTOS_STACK_SIZE, RTOS_TASK_PRIORITY, task_copy};
   cpp_freertos::Queue size_queue{RTOS_MAX_QUEUE_ENTRY_COUNT, sizeof(size_t)};
   audio_tools::SynchronizedBufferRTOS<uint8_t> buffer{0}; // size defined in constructor
   bool task_started = false;