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/hello_world/ta/Android.mk b/hello_world/ta/Android.mk
new file mode 100644
index 0000000..a1ff14a
--- /dev/null
+++ b/hello_world/ta/Android.mk
@@ -0,0 +1,4 @@
+LOCAL_PATH := $(call my-dir)
+
+local_module := 8aaaf200-2450-11e4-abe2-0002a5d5c51b.ta
+include $(BUILD_OPTEE_MK)