examples: add initial examples for RFC

Add hello_world and random(generate UUID) examples

Reviewed-by: Etienne Carriere <etienne.carriere@linaro.org>
Reviewed-by: Jerome Forissier <jerome.forissier@linaro.org>
Signed-off-by: Igor Opaniuk <igor.opaniuk@linaro.org>
diff --git a/Android.mk b/Android.mk
new file mode 100644
index 0000000..5053e7d
--- /dev/null
+++ b/Android.mk
@@ -0,0 +1 @@
+include $(call all-subdir-makefiles)