SafeDetect / Mbed OS tx_serial_from_pi

this works for reading in data from pi via usb

Diff: .gitignore

Revision:
2:8834f9351e9b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/.gitignore	Thu Jul 28 23:13:54 2016 +0100
@@ -0,0 +1,4 @@
+.build
+.mbed
+projectfiles
+*.py*