Small example using ultrasonic

Dependencies:   mbed

Revision:
2:00f96140b44b
Parent:
1:8fafe8a483e9
--- a/Adafruit_GFX.lib	Wed Nov 22 21:36:59 2017 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,1 +0,0 @@
-http://mbed.org/users/nkhorman/code/Adafruit_GFX/#8555740e27da