[stm32f429i-discovery] Moved Chucks example to usart_console

Chucks example is more elaborate than the simple ported example so we
keep both.

examples/stm32/f4/stm32f429i-discovery/usart_console/README

@@ -0,0 +1,9 @@
+Simple USART Example
+--------------------
+
+This example sets up a USART port and provides a few simple
+character handling functions to that a short interactive program
+can be demonstrated. It re-uses the clock setup from systick_blink
+and that means you could do times delays but that aspect isn't used.
+
+After this example we do character handling with interrupts.