Add a VERSION define

Makefile

@@ -6,8 +6,10 @@ PORT =  /dev/cu.usbmodem1421
 ARDUINO_LIBS = 
 #ARDUINO_CORE_PATH = hardware/keyboardio/cores/keyboardio
 #ALTERNATE_CORE = keyboardio
+GIT_VERSION := $(shell git describe --abbrev=4 --dirty --always)
 include _Makefile.Master
 
+
 astyle:
 	astyle --style=linux ArduinoKeyboard.ino *.h
 

_Makefile.master

@@ -352,6 +352,13 @@ ifdef EXT_C_FLAGS
 endif
 
 # Add extracted variable to compiler flags.
+#
+
+
+ifdef GIT_VERSION
+    EXTRA_FLAGS += -DVERSION=\"$(GIT_VERSION)\"
+endif
+
 ifdef BUILD_BOARD
     EXTRA_FLAGS += -DARDUINO_$(BUILD_BOARD)
 endif