Basic starter project - no switch bounce - crude blocking

Revision:
5:ac0eea152e50
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed_app.json	Wed Sep 18 10:45:11 2019 +0000
@@ -0,0 +1,3 @@
+{
+    "requires": ["bare-metal"]
+}
\ No newline at end of file