add new command to idf

examples/get-started/sample_project/main/CMakeLists.txt

@@ -0,0 +1,2 @@
+idf_component_register(SRCS "main.c"
+                    INCLUDE_DIRS ".")

examples/get-started/sample_project/main/component.mk

@@ -0,0 +1,5 @@
+#
+# "main" pseudo-component makefile.
+#
+# (Uses default behaviour of compiling all source files in directory, adding 'include' to include path.)
+

examples/get-started/sample_project/main/main.c

@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+void app_main(void)
+{
+
+}