add apploader example

applications/app-loader/app-loader.c

@@ -0,0 +1,18 @@
+#include "flipper.h"
+
+/*
+render_loader
+
+handle_input
+
+handle_menu
+*/
+
+void app_loader(void* p) {
+    osThreadId_t self_id = osThreadGetId();
+    assert(self_id);
+
+    printf("[app loader] start\n");
+
+    osThreadSuspend(self_id);
+}