Test program for AccurateWaiter

Dependencies:   SerialStream AccurateWaiter

This test program shows how to use AccurateWaiter and demonstrates its performance.

Here's what it looks like running on a NUCLEO_F429ZI: https://app.box.com/shared/static/a7vuulqeqodh7pn5skgvniwo0b4h3pmj.png

Revision:
0:df183df60d24
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed_app.json	Thu Nov 12 23:17:01 2020 -0800
@@ -0,0 +1,8 @@
+{
+    "target_overrides": {
+        "*": {
+            "platform.stdio-baud-rate": 115200,
+            "target.printf_lib": "std"
+        }
+    }
+}
\ No newline at end of file